How a legal basement apartment performs as an investment.

A legal basement apartment is a construction project, but it's also an income asset. This calculator gives a preliminary estimate of how long it takes to recover the project investment through rental income, and what the 10-year cumulative income looks like.

The figures here are intentionally simple — they reflect gross rental income against project cost, not a complete financial breakdown. A detailed projection that includes financing costs, insurance, utilities, vacancy, and maintenance is part of every site assessment we conduct.