CRE Due Diligence: Red Flags That Kill Deals and How Smart Buyers Catch Them

Use the gap to lock down access and documents. Before signing, negotiate a due diligence period long enough for third-party reports (commonly 30–60 days), a clear list of seller deliverables (rent roll, T-12, leases, service contracts, tax bills, prior reports), and a financing contingency. Items that most often trigger renegotiation or a walk-away are income that doesn't tie to bank deposits, roof and HVAC replacements in the PCA, Phase I findings, title or survey problems, and estoppels that contradict the rent roll.

Every issue you miss before closing becomes your cost after closing. Once the due diligence period expires, the earnest money usually goes hard, the price is locked, and environmental contamination, deferred maintenance, unrecorded lease rights, or overstated income become the buyer's problem. The cost of a Phase I, property condition assessment, survey, and lease audit, often several thousand to tens of thousands of dollars combined, is small next to a capital call or a lender default. Speed should come from preparation, not from skipping steps.

The same way as a marketed deal, but with more skepticism. Off-market sellers often have no offering memorandum, so the buyer must build the numbers from source documents: leases, a trailing 12-month operating statement, bank statements, tax bills, and utility history. Ask why the owner is selling quietly, check comparable sales and rents independently, and keep a full due diligence period in the contract. An off-market price is only a deal if the property survives the same inspections as any other.

Diligence the sponsor first, then the deal. Check the sponsor's full-cycle track record, how much of their own capital is invested, fee structure, and how they handled past problems. Then review the property-level work they did: third-party reports, rent roll and T-12 verification, debt terms, rate cap or maturity risk, and whether projected rent growth and exit cap rates are supported by comps. Read the private placement memorandum and operating agreement with an attorney before wiring funds.

Start with whether the in-place income is real and durable. That means verified occupancy, tenant credit, lease expirations, and expenses that match reality, followed by the physical condition, location fundamentals, and the debt the property can actually support. Price comes last: a low price on a building with a major lease rollover or a failing roof is not a bargain. Carson's The Red Flag Playbook is organized around exactly this order: income, structure, title, environment, and seller behavior.

Yes, and it covers five workstreams. Financial: rent roll, T-12, bank deposits, utility bills, tax bills. Leases: a sample or full lease audit, deposits, concessions, delinquency. Physical: property condition assessment and unit walk of every unit, roofs, plumbing, sewer scope, life-safety systems. Legal: title commitment, ALTA survey, zoning report, certificate of occupancy, code violations. Environmental: Phase I ESA, plus mold, asbestos, and lead-based paint for older buildings. The checklist section on this page breaks these out by workstream.

Yes, as a first-pass tool, not a replacement for professionals. AI can abstract leases, compare rent rolls to signed leases, flag CAM and escalation inconsistencies, summarize title exceptions, and scan Phase I reports for recognized environmental conditions. It can also miss context or produce confident errors, so every material finding should be checked against the source document and confirmed by the attorney, surveyor, environmental consultant, or lender who is accountable for it.

Hire for the property type, not convenience. Ask for sample reports on similar buildings, licenses and insurance (including errors and omissions coverage), and whether they use specialists for roofs, sewer scoping, and HVAC. For commercial assets, use a firm that writes property condition assessments to ASTM E2018 with cost tables for immediate and short-term repairs. Avoid relying on an inspector referred only by the seller's side, and request photos and video so you can review findings remotely.

Rebuild income from evidence the seller can't easily edit. Match the rent roll to signed leases, then tie 12 months of collections to bank deposit statements; request tax returns, which show what the owner reported to the IRS. Interview or survey tenants, run tenant estoppels, and check utility bills against claimed occupancy. A 100% occupancy rent roll with weak bookkeeping is itself a red flag. If income can't be verified, underwrite only what you can prove and price the deal accordingly.

Underwrite your own NOI and price off that number. Listing NOI is often based on pro forma rents, omits management fees, reserves, or repairs, or uses a pre-reassessment tax bill. Rebuild it from the T-12 and rent roll, add a market management fee and replacement reserves, and adjust property taxes for the post-sale assessment. If the gap is material, renegotiate the price using your NOI and the market cap rate, or walk away.

Property taxes, insurance, and in-place rents are the three that most often break underwriting. Taxes may reset to the purchase price after the sale, insurance premiums have risen sharply in many markets, and rents on the rent roll may include concessions or tenants who aren't paying. Also verify lease expiration dates, the exit cap rate assumption, and the loan's debt service coverage at current interest rates, not the rate on the seller's old loan.

Yes. Signed leases show what tenants actually agreed to pay, while asking rents show what landlords hope to get. Asking rents ignore free rent, tenant improvement allowances, and other concessions that lower effective rent, so underwriting off them overstates income. Use recent signed leases for similar space, adjusted to effective rent, and treat a seller's pro forma that relies on asking rents as an assumption to test, not a fact.

Often, yes. Having your own buyer's representative helps on a deal where information is controlled. It's common for a listing broker to require a signed NDA or LOI before releasing full financials, but a reasonable LOI should be non-binding and conditioned on review of the rent roll, operating statements, and leases during due diligence. A buyer-side broker can push for documents, pull independent comps, and keep the due diligence period from being shortened. Never let missing financials pressure you into a hard deposit.

Look for chronic late payment, rent below or far above market, recent concessions, side agreements, related-party tenants, and leases expiring together. Compare each lease to the rent roll, check delinquency reports and security deposits, and review tenant financials or credit for larger tenants. Watch for options to terminate, renew below market, or buy the property (rights of first refusal). Tenant estoppels confirm these terms in writing before closing.

Lease term is the main value driver, so a short remaining term means more risk and a lower price. Find out whether the tenant has renewal options, how much it has invested in the site, whether the location is strategic for its network, and what re-leasing would cost in downtime, tenant improvements, and commissions. Lenders may also limit loan terms to the remaining lease. Price the deal on a realistic vacancy scenario, not just the current rent.

It's normal for a lender to require an estoppel and an SNDA (subordination, non-disturbance, and attornment agreement); it's not normal for an estoppel to rewrite the lease. An estoppel should confirm existing facts: rent, term, defaults, and deposits. Subordination belongs in the SNDA, which should include non-disturbance protection for the tenant. If a lender's form changes lease terms, tenants will often refuse or mark it up, and the parties should handle real changes through a lease amendment.

Use the lease and the seller. Most commercial leases require tenants to deliver an estoppel within a set period, often 10 to 30 days, so the purchase contract should make the seller responsible for requesting and delivering signed estoppels as a closing condition. Send a short, factual form early, pre-filled with lease terms, and give tenants a contact for questions. Residential tenants usually have no obligation, so buyers often use a simpler tenant questionnaire instead.

A basic estoppel confirms the lease documents and amendments, commencement and expiration dates, current base rent and additional rent, the paid-through date, the security deposit, any prepaid rent, renewal or purchase options, and whether either party is in default. It should also confirm there are no side agreements and that the tenant has no offsets or claims against the landlord. Have your attorney adapt a form to the lease's estoppel clause rather than relying on a generic template.

Landlords bill tenants estimated monthly CAM, tax, and insurance charges, then compare those estimates to actual costs after year-end and bill or credit the difference. The lease controls what's recoverable, the tenant's pro rata share, caps, exclusions, and the reconciliation deadline. During due diligence, review the last two or three reconciliations, confirm they were delivered on time, and check for unbilled balances or tenant disputes, because those claims transfer to the buyer.

The latest signed amendment generally controls, so billing from the original share is an error to fix. Expansions, contractions, or building remeasurements change a tenant's pro rata share, and overcharges or undercharges can carry over for years. A lease audit should recalculate every tenant's share from the current leasable area and the most recent amendment. Under-billing may be uncollectible past the lease's look-back period, and over-billing creates a refund claim the buyer may inherit.

Address them in the purchase contract before closing. Identify every year that hasn't been reconciled, estimate the amounts owed to or by tenants, and decide who keeps the true-up. Common solutions are a closing proration, a seller holdback or escrow, or a seller obligation to complete past reconciliations. Without that language, the buyer may face tenant refund demands or be unable to collect amounts the seller never billed.

Yes, if the contract includes a due diligence or inspection contingency. As-is usually means the seller won't make repairs or give condition warranties, not that the buyer can't renegotiate. The leverage is your right to terminate during the due diligence period. Present the findings with contractor bids and ask for a price reduction or closing credit, which sellers usually prefer over repairs. Once the contingency expires, that leverage is gone.

Get specialist opinions and real repair bids before the due diligence period ends. A structural engineer and a sewer scope contractor can tell you whether the issue is cosmetic, progressive, or a major repair. Then choose: request a price reduction or credit that covers the repair plus a contingency, request a deadline extension for further study, or terminate. Don't close on a structural issue without knowing the cost, and confirm the lender and insurer will accept it.

Structural failure, roof replacement, failing sewer lines, and environmental contamination are the findings most likely to end a deal outright. Others include outdated electrical systems, fire and life-safety deficiencies, ADA issues, and large HVAC replacement costs. These items are expensive, hard to finance, and can affect insurability. A good property condition assessment prices immediate and near-term repairs so you can decide whether a renegotiated price still works.

Many of the biggest risks: tenant quality, neighborhood trajectory, management practices, deferred maintenance behind locked doors, drainage problems, and the reason the seller is leaving. Walk every unit or suite, visit at night and on weekends, talk to tenants and nearby owners, and call the local code and zoning office. Financial statements show what happened; a site visit shows what's likely to happen next.

No. Auto body and repair uses are classic environmental red flags because of solvents, paints, waste oil, floor drains, and possible underground storage tanks. Wait for the Phase I ESA under ASTM E1527-21; completing it before acquisition is also required to preserve CERCLA landowner liability defenses. If it identifies recognized environmental conditions, a Phase II with soil or groundwater sampling may be needed. Extend the due diligence period if necessary rather than closing blind.

It means the legal use may not match the actual use. Lenders and appraisers generally value only legally permitted units, so the extra residential units may not count toward income, and the property may need a commercial or mixed-use loan rather than a residential loan. Illegal units can also create code, insurance, and liability exposure. Confirm the legal unit count with the building department before closing and price the deal on the legal configuration.

Yes, but make the ruling a contract condition. Structure the offer with a due diligence or zoning contingency that lets you terminate if the ruling is unfavorable, or extend closing until it's issued. Order a zoning report, review the use history, and consult a land-use attorney about rezoning or variance odds. Price the deal on the use you can legally operate today, not the use you hope to win.

Yes. A legally nonconforming use or structure, often called grandfathered, generally runs with the land and can transfer to a buyer. The key risks are that local rules may end the status if the use is abandoned for a set period or the building is substantially destroyed, and lenders may limit financing. Sellers should provide a zoning verification letter or zoning report, and buyers should confirm rebuild rights and insurance coverage, including ordinance-or-law coverage.

Treat it as a red flag until a survey resolves it. For example, 1.07 acres is about 46,600 square feet while 4,648 square feet is about 0.107 acres, which suggests a decimal error, but you can't assume which figure is right. Order an ALTA/NSPS survey, compare it to the legal description in the deed and title commitment, and check the recorded plat. Price and contract terms should be based on the surveyed land area.

Possibly, depending on your title policy and survey. A standard owner's policy usually excludes survey matters, but extended coverage or a survey endorsement may cover the encroachment. A surveyor's errors and omissions coverage may apply if the survey missed it, and the seller may be liable under deed warranties. Notify the title insurer in writing promptly and have a real estate attorney review options such as a boundary agreement, easement, or claim.

No. Assessor records are for tax purposes and are often outdated or incorrect. Confirm the legal unit count through the certificate of occupancy, building permits, and the zoning office, and check whether any units were added without permits. Lenders, appraisers, and insurers will rely on the legal count, so an unpermitted unit can reduce value, financing, and income.

When the inconsistencies affect income, control, or legal rights and the seller won't fix them in writing. An undisclosed lease can bind the buyer as the new owner, so it's a serious issue. Require a full lease schedule, estoppels from every occupant, and contract representations that the disclosed leases are complete. If the story keeps changing or the seller resists verification, walking away is usually cheaper than litigation later.

Ask directly and verify. Find out why the seller is selling, whether there is a loan maturity, partner dispute, estate issue, or lender approval needed, and whether all owners have signing authority. Check recorded loans, liens, lis pendens, and entity records. Pre-clear your lender's requirements and timeline early. Deals with good numbers often fail because one party needs a different price, timing, or tax outcome.

Identify whether the distress is operational, physical, financial, or locational. Poor management or overleverage can be fixed; failing structures, crime, or a weak submarket are harder. Review delinquency and turnover, capital needs from the property condition assessment, code violations, and loan default or maturity issues. A distressed property is a deal only if the purchase price plus the full cost and time to stabilize still beats buying a stabilized asset.

Due diligence periods are negotiated in the purchase contract, commonly 30 to 60 days and up to about 90 for complex or financed deals. The core reports are a Phase I environmental site assessment (ASTM E1527-21), a property condition assessment (ASTM E2018), an ALTA/NSPS survey, a title commitment, a zoning report, flood zone determination, and lease and estoppel review.

Before the letter of intent is signed, or at the latest in the first week of due diligence, while there is still time to order reports and renegotiate. Red flags found early can be priced or fixed; red flags found the day before the contingency expires usually mean walking away. Carson Jones reviews deals for buyers; contact him here.