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House hacking a starter home means you live in part of the property and rent the rest. On a duplex, triplex, or fourplex, you run two models: cash flow while you occupy one unit, and the cap rate if every unit were rented.
By RentalAnalytics Editorial Team · Published October 5, 2026
Those results will not match. One answers what it costs to live there. The other answers what the building earns as a rental if you leave. This guide is educational. It quotes no down-payment minimums and no market rents.
This walkthrough uses a small multi-unit you buy to occupy. You live in one unit and lease the others. Rental income offsets part of the cost of the whole building.
Renting rooms in a single-family house is a related plan with less stable income. The steps below stay with separate units, where the two tools map cleanly.
You are a resident and an owner. The resident cares about cash after the other units pay in. The owner cares whether the price makes sense if every door is rented later. You need both views.
Build one fact sheet first.
Debt service comes from your Loan Estimate or a written quote. This article does not state a required down payment. If you have no quote yet, leave the payment blank and finish the cap rate first. Cap rate does not need the loan. Cash flow does.
Open the cash flow analyzer.
Income is rent from the other units, plus other income you already collect. The rent you no longer pay a landlord elsewhere is personal savings. Note it beside the sheet if you want. Keep it out of property income.
Vacancy applies to the leased units. Your unit is occupied by you. If a lease ends soon, do not model the whole year at a renewal you have not signed.
Expenses cover the whole building. Taxes, insurance, repairs, utilities you pay, and dues do not shrink because you sleep in one unit. Check heat, water, and electric. One meter often serves more than one household. Enter only the share you still pay.
Management can be zero in this scenario if you will self-manage while you live there. Label that assumption. The day you move out, zero becomes a fee or your unpaid hours. Do not reuse zero in the full-rental model without a new decision.
Debt service is the full payment on the quote. If taxes and insurance sit inside escrow, do not subtract them again as separate lines.
Add a reserve for shared systems. The result is property cash flow during occupancy. Save the run before you test another rent or another quote.
Cap rate is the yield before debt at the price you pay, assuming a normal rental.
Open the cap rate calculator. Use market rent on every unit, including yours, and label your unit as a comp-based estimate. Keep leased units on their contracts unless you are testing renewals. Subtract vacancy on the full building, because your door can sit empty after you leave. Subtract operating expenses for a rental operation, including management if you will hire it.
NOI divided by purchase price is the cap rate. If you also divide by price plus closing costs plus immediate repairs, name that second figure. Do not call both of them the cap rate.
Leave the occupancy loan out of this math. Financing lives in the cash flow model. If a lender has written an investor payment for after you move out, test that as its own row. If you have no quote, skip the row.
Counting avoided rent as collected income. Using one rent figure for leased units and for a unit that only has comps. Ignoring a shared roof. Freezing taxes at the pre-sale bill when you expect a reassessment. Copying a single-family premium into a multi-unit file. Setting repairs to zero because you will live there for a year. Testing a refinance nobody offered.
Living next door also does not remove screening, deposit, and registration duties on the units you lease. Read the local rules before you rely on the income.
Read cash flow as the occupancy plan. If it is tight, name the line: a vacant rented unit, owner-paid heat, taxes, insurance, or the payment. Change one supported input, rerun, and record the difference.
Read the cap rate as the price check with your unit at market rent and a normal expense load. A hack that only works because your rent is zero and repairs are blank is a housing choice with a concentrated building risk. It can still be the right place to live. Describe it that way until the full-rental model is filled in.
When both tools use the same fact sheet, you can say what you expect to pay or receive while you live there, what cap rate you get at full rent, and which assumption would break either result. Load the leases and the quote into the cash flow analyzer and the cap rate calculator before you treat the starter home as a hack that pays you to live there.
Not as collected income, while you live there and do not pay yourself rent. Put market rent on that unit in the cap rate model and mark it as an estimate. Keep any avoided rent outside property income.
They answer different cases. Occupancy cash flow uses partial rent and your payment. Cap rate uses full rental income and no debt service. Read the labels. Do not average the outputs.
You can set the management fee to zero in the occupancy scenario if you will truly self-manage, with that label on the row. Repairs are still real. Unpaid labor does not fund a roof. Keep a repair line and a reserve.
The terms on your Loan Estimate for this property and this occupancy. If the quote is not in hand, leave debt service blank.
They can move cash flow more than a small rent gap. Enter the meters and the lease splits, then put only your share in the analyzer. Recheck the split when a lease ends.
It means the other units cover a large share of the carrying cost under this loan and this residency. The cap rate, with your unit at market rent, is the check on price. Run both.
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