Three tests before you put money in. Fail one, walk or renegotiate.
Does it fit what you wrote down before you looked? Rentals all in at 70% of value or less. Flips all in at 80% or less with profit cushion.
Your own comps, every cost. Rehab over, timeline slips, ARV low. Does it still work?
Money lined up, contractor with an itemized scope and signed agreement, a known exit.
Walking is a win when the numbers fail.