Read a 2 to 4 unit cash flow before you write the offer.

What this screen is for

Use it on a residential duplex, triplex, or fourplex before you treat a single rent figure as the building. The buyer view walks the building, the income, the costs, the loan, and the decision in plain language. The realtor view keeps every input and shows a shorter result the agent can save on this browser, copy as a link, or print to PDF. Switching views does not change the math.

The rental NOI and DSCR calculator is the single-rent companion. This page adds the unit split, the capital reserve as its own layer, and an owner-occupant loan screen.

How the layers stay separate

Gross income is unit rent plus other income such as laundry or parking. Vacancy, maintenance, and property management are percents of gross unit rents, not of other income. Operating expenses are taxes, insurance, optional HOA, maintenance, and management. NOI is effective gross income minus those operating expenses. Cap rate is NOI divided by the purchase price.

The capital reserve defaults to 1 percent of the purchase price per year and is subtracted after NOI. Principal and interest, plus mortgage insurance, come off after that. Cash flow is the bottom line. Operations DSCR is NOI divided by principal and interest. Cash DSCR uses NOI after the reserve, divided by principal and interest plus mortgage insurance. Points are part of cash invested. A zero loan shows debt coverage as not applicable instead of dividing by zero.

Owner-occupant loan screen

The FHA scenario sets 3.5 percent down and finances a 1.75 percent upfront mortgage insurance premium into the note. Annual mortgage insurance follows Mortgagee Letter 2023-05. The table threshold used here is the 2026 one-unit baseline conforming loan limit of $832,750 published by FHFA on November 25, 2025. Handbook 4000.1 requires at least one borrower to occupy within 60 days and intend to continue occupancy for at least one year. A decision credit score under 580 changes the minimum required investment. This page does not know the credit score.

For a three- or four-unit FHA file, the self-sufficiency test compares the full monthly housing payment with net rent. Handbook 4000.1 uses the appraiser's fair market rent from all units, including the unit the borrower will occupy, minus the greater of the appraiser's vacancy and maintenance estimate or 25 percent. This screen uses the market rent you type for your unit. If you set the haircut under 25 percent, the result is marked as your override.

Counted qualifying rent is different. Handbook 4000.1 says subject-property rental income is added to income and may not reduce the mortgage payment. With limited rental history, the mortgagee uses 75 percent of the lesser of appraiser fair market rent or the lease. Freddie Mac's seller guide uses 75 percent of the gross rent from the units the borrower will not occupy, and adds that net rental income to stable monthly income while the housing expense is calculated without it. This screen adds your stated income to the counted percent of the other units only, then compares the full housing payment and your other monthly debts. It does not have the appraisal or the lease.

Fannie Mae's Eligibility Matrix dated August 5, 2026 shows 95 percent loan-to-value for a 2 to 4 unit principal residence purchase under Desktop Underwriter. Manual underwriting and high-balance loans are lower. Freddie Mac's published maximum LTV chart shows 95 percent for an Accept mortgage on a 2 to 4 unit primary residence, 85 percent manual or super conforming on a 2-unit primary, and 80 percent manual or super conforming on a 3- or 4-unit primary. A 2 to 4 unit investment purchase is 75 percent on both charts. The conventional button on this page only sets a 5 percent down payment and a 0.50 percent mortgage insurance allowance so you can see the cash. That allowance is not an insurer quote. None of these buttons is an eligibility finding.