Investor Guide · Due Diligence
The LA Multifamily Due Diligence Checklist
Due diligence on an LA apartment building breaks into five areas: financial, physical, legal & regulatory, title, and tenant. In LA, the deal-killers are rent-control compliance, unpermitted units, soft-story retrofits, and a property-tax reassessment that quietly wrecks the pro forma.
The Process
Five areas, one disciplined process
1
Financial
Verify every dollar of income and expense.
2
Physical
Inspect the building top to bottom.
3
Legal & Regulatory
RSO, AB 1482, permits, and Measure ULA.
4
Title & Ownership
Liens, easements, and clear title.
5
Tenant & Operational
Leases, estoppels, and security deposits.
In California, your purchase contract gives you a 17–30 day due-diligence (contingency) period to investigate everything below and walk away with your deposit if it doesn't check out. Use every day of it.
Area 01
Financial due diligence: verify, don't trust
The seller's marketing pro forma is a best case. Your job is to confirm what the building actually earns.
✓
Certified rent roll: every unit, tenant, actual rent, lease dates, deposit.
✓
Trailing 12-month (T-12) operating statements: real numbers, not projections.
✓
Bank statements and proof of collected rent; tie deposits to the rent roll.
✓
All leases & addenda, plus signed estoppel certificates from each tenant.
!
Property-tax reality check (Prop 13): your purchase reassesses the building to your price, so taxes reset to roughly 1.1%–1.25% of what you pay, often far above the seller's bill. Underwrite your tax figure, not theirs.
✓
12 months of utility bills, service contracts, and insurance loss runs.
Area 02
Physical due diligence: inspect everything
✓
General commercial inspection plus unit-by-unit interior access.
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Roof age and condition; plumbing (galvanized supply, clay sewer laterals); electrical panel and wiring.
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Foundation and structure; pest and termite report; deferred-maintenance cap-ex.
!
Soft-story retrofit: many older wood-frame buildings with tuck-under parking must be seismically retrofitted. Confirm whether it's complete, pending, or not started; an open retrofit is a five- to six-figure cost you inherit.
Area 03
Legal & regulatory: where LA deals live or die
This is the section most out-of-area buyers underestimate.
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Rent-control applicability: LA City RSO (C of O before Oct. 1, 1978) vs. California AB 1482 (most other buildings 15+ years old).
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RSO registration status; rent-overcharge exposure from past increases; relocation-assistance obligations.
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Unpermitted “bootleg” units: common in LA. Income you may not legally collect, a lender red flag, and a code liability. Verify the legal unit count against the certificate of occupancy.
✓
Measure ULA awareness: LA City's transfer tax applies above $5.4M (4%) and $10.9M (5.5%) as of July 1, 2026, paid by the seller on gross price.
Area 04
Title & ownership due diligence
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Preliminary title report: confirm clear ownership; identify liens, judgments, unpaid taxes.
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Easements & encroachments; shared driveways and access are common on dense LA lots.
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Survey / ALTA for larger deals; CC&Rs and zoning to verify legal use and any nonconforming status.
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Phase I Environmental Site Assessment on larger or commercially adjacent properties.
Area 05
Tenant & operational due diligence
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Security-deposit reconciliation; deposits transfer to you at closing, so confirm the amounts.
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Section 8 / HACLA tenancies; confirm contracts, inspection status, and contract rents.
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Pending litigation or tenant complaints; real vacancy and turnover history.
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On-site staff and management transition at close.
Memorize These
The five LA-specific traps
1
Prop 13 reassessment
Budget your property taxes (~1.1%–1.25% of price), not the seller's.
2
Soft-story retrofit
Confirm status before you're on the hook for a five- or six-figure cost.
3
Unpermitted units
Phantom income and a financing or code-enforcement liability.
4
RSO over-charges & registration gaps
Inherited rent liability that follows the building to you.
5
Measure ULA
Shapes pricing and your eventual exit, even as a buyer.
For Owners & Sellers
Selling instead? Get “due-diligence ready” first
The fastest way to lose money on a sale is to let a buyer discover problems mid-escrow and re-trade your price. Owners who organize the rent roll, square up RSO registration, and document retrofit status hold their price and close faster, part of how we maintain a 97.6% list-to-sale ratio.
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Frequently asked questions
How long is the due-diligence period when buying an LA apartment building?
Typically 17 to 30 days in California, defined by your purchase contract's contingency period. During it you can investigate the property and cancel for your deposit back if it doesn't check out.
What documents should I request during multifamily due diligence?
At minimum: a certified rent roll, trailing 12-month operating statements, all leases and addenda, estoppel certificates, bank statements, 12 months of utility bills, service contracts, insurance loss runs, and the preliminary title report.
What is an estoppel certificate?
A document each tenant signs confirming their actual rent, deposit, lease terms, and that no undisclosed side agreements exist, protecting you against an inaccurate rent roll after closing.
Will my property taxes go up when I buy in California?
Yes. Under Proposition 13, your purchase reassesses the property to your purchase price, so taxes typically reset to roughly 1.1%–1.25% of the price, often above the seller's current bill. Always underwrite your own tax figure.
What is the LA soft-story retrofit requirement?
Los Angeles requires many older wood-frame buildings with ground-floor soft story (often tuck-under parking) to be seismically retrofitted. Confirm whether a building's retrofit is complete, pending, or not started, as it can cost tens of thousands of dollars.
How do I check if an LA building is under rent control?
Check the certificate-of-occupancy date: LA City RSO generally applies to buildings issued a C of O before Oct. 1, 1978, while most other buildings 15+ years old fall under California AB 1482.
What are unpermitted units and why do they matter?
Bootleg units added without permits are common in LA. They can be income you can't legally collect, a lender red flag, and a code-enforcement liability. Verify the legal unit count against the certificate of occupancy.
Does Measure ULA affect me as a buyer?
Usually not directly; the LA transfer tax is paid by the seller on sales above $5.4M. But it influences pricing, negotiation, and your future exit, so factor it into underwriting.
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We flag the LA-specific risks before they cost you, on either side of the deal.
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