Duplexes, triplexes, and fourplexes qualify under residential 1-to-4-unit DSCR guidelines using Fannie Mae Form 1025 (Small Residential Income Property Appraisal Report). Underwriters sum the qualifying gross monthly rent across all two, three, or four units—using the lesser of executed leases or market rent per unit—and divide that combined total by the property's single monthly PITIA payment.
For real estate investors seeking higher cash flow density without stepping into complex commercial loan covenants, small 2-to-4-unit multifamily properties sit in the sweet spot of the wholesale mortgage market. Because two-, three-, and four-unit buildings are legally classified as residential collateral, they enjoy 30-year fixed rates, no commercial annual financial audits, and gross-rent PITIA underwriting rather than Net Operating Income (NOI) haircuts. However, underwriting a multi-unit property introduces unique appraisal, lease-blending, and leverage rules that differ from single-family homes.
How Do Underwriters Blend Leased and Vacant Units on Form 1025?
When you finance a single-family rental, the appraiser completes Form 1004 along with a Form 1007 rent schedule. On a duplex, triplex, or fourplex, the appraiser instead completes Form 1025, which includes both comparable multi-unit sales and a unit-by-unit comparable rental grid.
In real-world acquisitions, it is common for a triplex or fourplex to have two or three occupied units on active leases and one vacant unit undergoing turnover or renovation. Wholesale DSCR underwriters handle mixed occupancy by evaluating each unit individually and then aggregating the qualifying rent:
- Occupied Units With Executed Leases: Typically underwritten at the lesser of the in-place lease amount or 100% of the appraiser's Form 1025 market rent opinion for that specific unit configuration. (Some wholesale matrices permit using a higher in-place lease up to 110% or 115% of market rent if you document two to three months of cleared rent payments.)
- Vacant Units at Closing: Typically underwritten at 100% of the appraiser's Form 1025 market rent on purchases, provided the unit is in rent-ready C1–C4 condition. On cash-out or rate-and-term refinances, select wholesale lenders apply a 5% LTV reduction or require at least 50% to 75% of the building's units to be leased at closing.
Let's walk through a worked example of a brick fourplex in St. Louis, Missouri, purchased for $480,000 at 75% LTV ($360,000 loan amount). Assume your total monthly PITIA equals $3,120:
| Unit Number | Bed / Bath Layout | Occupancy Status at Closing | In-Place Signed Lease | Appraiser Form 1025 Market Rent | Underwriter Qualifying Rent |
|---|---|---|---|---|---|
| Unit 1A | 2 Bed / 1 Bath | Occupied (long-term tenant) | $925 / month | $1,050 / month | $925 / month (capped by lease) |
| Unit 1B | 2 Bed / 1 Bath | Occupied (newly leased) | $1,075 / month | $1,050 / month | $1,050 / month (capped by 1025) |
| Unit 2A | 2 Bed / 1 Bath | Vacant (turn-key updated) | $0 (Vacant) | $1,050 / month | $1,050 / month (100% market rent) |
| Unit 2B | 1 Bed / 1 Bath | Occupied (renewed lease) | $875 / month | $875 / month | $875 / month (matches market) |
| Building Total | 4 Residential Doors | 75% Physical Occupancy | $2,875 In-Place | $4,025 Full Market | $3,900 Qualifying Gross Rent |
Dividing the $3,900 qualifying gross rent by the $3,120 monthly PITIA yields an underwritten 1.25 DSCR. Notice two critical lessons from this table: first, Unit 1A's legacy below-market lease ($925) constrains that unit's qualifying income unless the unit is delivered vacant at closing; second, the vacant turn-key Unit 2A receives full $1,050 market rent credit on a purchase transaction, allowing the building to clear the 1.20+ top pricing tier easily.
How Do LTV Limits and Pricing Differ Between 1-Unit and 2-4 Unit Properties?
While duplexes, triplexes, and fourplexes use the same residential DSCR loan application as single-family homes, wholesale lenders treat 2-to-4-unit collateral as slightly higher risk in secondary-market securitizations. You should expect two standard adjustments across most wholesale matrices:
- Maximum LTV Caps: Where a strong-credit borrower (720+ FICO) might qualify for 80% LTV on a single-family purchase, roughly half of wholesale DSCR lenders cap 2-to-4-unit purchases at 75% LTV (though select top-tier shelves still allow 80% LTV on duplexes and 75% on 3–4 units). For cash-out refinances, maximum leverage on 2–4 units commonly sits between 70% and 75% LTV.
- Loan-Level Price Adjustments (LLPAs): Wholesale rate sheets typically add a multi-unit collateral adjustment of 0.250 to 0.750 points in fee (or roughly 0.125% to 0.250% in note rate) for duplexes, and slightly more for triplexes and fourplexes. Even with that modest adjustment, the combined rent from multiple doors almost always produces a much stronger DSCR and net cash yield than a single-family house at the same price point.
Underwriting Watchout: Never confuse a 1–4 unit residential DSCR program with a 5+ unit commercial program. Once a building has five or more units, the underwriting math switches from Gross Rent / PITIA to Net Operating Income / Debt Service. Read our full comparison of 1-4 unit residential vs 5-8 unit commercial DSCR loans to see how that boundary works.
What Property Configuration Red Flags Should Investors Screen on 2-4 Units?
Before submitting an offer on a small multifamily property, have a Loan Daddy loan specialist review the county property record card and zoning status for four common underwriting traps:
- Mixed-Use Commercial Space: If a building has one ground-floor retail shop and two upstairs apartments, it is classified as a mixed-use property rather than a standard residential triplex. Only select wholesale DSCR shelves finance mixed-use buildings, and they require commercial income documentation.
- Unpermitted Unit Conversions: A large Victorian single-family home divided into four apartments without separate electric meters, legal egress, or multi-family zoning compliance will be flagged by the appraiser on Form 1025 as an illegal use.
- Multiple Detached Structures on One Parcel: Two separate duplexes on a single tax parcel (four units total) are acceptable on many wholesale shelves, whereas four separate single-family cottages on one parcel may require specialized portfolio underwriting.
- International Ownership Structures: Non-U.S. citizens buying duplexes or fourplexes face stricter LTV ceilings—see our foreign national DSCR loan guidelines for details.
Ready to run the unit-by-unit numbers on a duplex, triplex, or fourplex? Check your eligibility with a Loan Daddy loan specialist to compare wholesale 2–4 unit matrices side by side.