Your profit = market sale price minus agent commission, transfer tax, closing costs, seller credit and any work you put in, minus what you tie the property up for with the seller. Market sale price starts from the as-is value and comes down for a softer market: 0% off in a good market, 5% off in an okay one, 10% off in a bad one. The three scenarios show what you'd clear at the same contract price if the market moves on you. Underwrite to the okay or bad column and a good market becomes upside, not a requirement.