This page comes last on purpose. It is for the end of the hunt, when two real homes are left on your shortlist and the choice will not settle itself — the same money into each, and very different money out.
Put the two homes you are torn between through the same arithmetic — typically the older one against the newer one. What you keep after maintenance, insurance and the reserve the older building quietly needs — and how a thin edge on paper disappears in practice.
Two buildings, same money in. What you actually pocket after upkeep, and how a thin edge on the old building vanishes.
The two things that come after the tie-breaker.