Your W-2 income is untouched by any of this. The whole question is whether we need the self-employment income to qualify you. If your W-2 job alone gets you to the payment you want, the Schedule C can stay out of the qualifying picture entirely, business loss and all. That is the cleanest path, and it saves documentation too. If you do need the self-employment income, underwriting counts whatever the tax return actually shows. A car write-off big enough to push the business into a loss means that income effectively contributes nothing to qualifying. We have seen a self-employed borrower whose return showed six figures of top-line revenue net down to a small paper loss after costs and expenses, which made including the business worse than leaving it off. Worth knowing: you are not required to claim every deduction available to you. If you need the income more than the tax savings, you can choose not to write off the vehicle. Talk to your tax advisor about that trade-off, since it is your tax bill on the line and only you can weigh the two. If you genuinely need the income and cannot avoid showing a loss, non-QM options exist. A bank-statement loan qualifies you off business deposits with an expense factor applied (illustratively somewhere in the 20 to 50% range), and it can sometimes run as a hybrid with your W-2 income, though it prices like a standard bank-statement loan. Which route costs least depends on your full picture. That is exactly what the free Roadmap conversation sorts out, about 20 minutes where we run your real numbers.