What happens if the other unit sits empty?
You cover the whole payment until it is rented again, and you can plan for that before you buy. Every Series listing shows the cost with and without the rent. Almost every rental sits empty between tenants at some point, and the lender is owed the same amount either way.
WHAT MOST PEOPLE ARE NEVER TOLD
The lender already plans for it. FHA's test on a triplex or fourplex sets aside at least 25 percent of the rent for "vacancies and maintenance", and some loans want months of payments saved.
On a conventional loan, Fannie Mae's automated system asks for six months of payments in reserve on a two-to-four unit home you live in. FHA asks for three months on a triplex or fourplex. Lenders can ask for more. Treat that money as a floor, and leave it alone after you move in.
An empty unit costs more than the missed rent: paint, cleaning, new locks, a listing, a screening report. The Series Homes book budgets half a month's rent to a full month for that, and plans on two empty months per unit every three years.
More units spread it out. In a house with an ADU or a duplex, one empty home is all of your rent. In a fourplex it is about a third.
GOOD TO KNOW
Before you buy, check that you could pay two months of the whole payment from savings. A low down payment lets you buy with little saved, so if two months would empty your savings, save more first and come back with a margin.
Yours is a little different. They all are.
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WHERE THIS COMES FROM
- Fannie Mae Selling Guide B3-4.1-01, Minimum Reserve Requirements
- HUD Handbook 4000.1 (FHA): II.A.1.b.iv(B)(3)(c) self-sufficiency test, II.A.4.d.i(C) reserves
- U.S. Census Bureau, Housing Vacancy Survey, Annual Statistics 2025, Table 12
- The House Hacking Bible, chapter 12: Vacancy, Turnover, and the Cost of Being Too Optimistic (Series Homes)
Researched and written by Series Homes. Checked against its sources on . Lending rules change. This page is general information, not a loan offer or legal or tax advice.