Small multi-family properties — duplexes, triplexes, and fourplexes — sit in a unique sweet spot for investors. You get the financing advantages of residential real estate (conventional loans, FHA, low down payments) with the income diversification of commercial property. One vacant unit doesn't stop your cashflow completely.
But the analysis is more involved than a single family home. Here's how to approach it correctly.
With a single family home, vacancy is binary — you either have a tenant or you don't. With a fourplex, one vacancy is 25% of your income, not 100%. That income redundancy changes the risk profile significantly.
It also changes the analysis. You're evaluating the building's total income-producing capacity, not just one unit. Market rents per unit, unit mix, and occupancy history all matter.
Start with the total potential rent if all units were occupied at market rate. Don't use the current rents if they're below market — calculate what you'd charge new tenants based on comparable rentals in the area.
Apply a vacancy allowance to the gross rent. For small multifamily, 8–10% is standard. If the market is tight and demand is strong, you can use 5%. Never model 0% vacancy — it's not realistic.
Subtract operating expenses from EGI to get NOI. For small multifamily, operating expenses typically run 35–50% of gross rent and include insurance, property taxes, repairs, maintenance, and management fees.
For 2–4 unit properties, cap rate is still the primary valuation metric — though some markets price small multifamily more like single family (on a per-unit or price-per-square-foot basis). Know which method buyers in your market use.
| Component | Value |
|---|---|
| Units | 4 × 2BR/1BA |
| Market rent per unit | $1,100/month |
| Gross annual rent | $52,800 |
| Vacancy (8%) | −$4,224 |
| Operating expenses (40%) | −$19,430 |
| NOI | $29,146 |
| Purchase price | $380,000 |
| Cap rate | 7.7% |
Always verify actual current rents against market rents. A fourplex with below-market rents might look like a poor deal on paper but represent significant upside once leases turn over.
Properties with 1–4 units qualify for residential financing — conventional loans, FHA (with owner-occupancy), and VA loans. This is a significant advantage over 5+ unit properties, which require commercial financing at higher rates with shorter amortization.
FHA loans allow 3.5% down on a property up to 4 units if you owner-occupy one unit. This is called "house hacking" — living in one unit while renting the others can dramatically improve your cash on cash return and reduce your entry cost.
Propivo covers 2–4 unit multi-family properties across all 50 states. Enter the property address and get live rent estimates based on comparable rentals in the area, estimated market value from recent comparable sales, and full Buy & Hold analysis with cap rate, cash on cash, and monthly cashflow calculated automatically.