your lender client is instructing you how to do the appraisal and that is wrong.
Cost to cure is an estimate by the appraiser what it would cost to repair defects and replace or update. But it does not describe the condition. The condition, average, good, poor , fair - you described it as poor, which usually means significant repair and deferred maintenance.
Sometimes you have to go further out to find a comp, though the listing sounds like one. Some poor condition homes are tear downs, others usually appeal to an investor/flipper and that determines teh lower price - look for higher priced flipped similar houses and see their prior sale price in poor or fair condition.
If you are using any superior condition comps, then you adjust for market reaction which is seen in prices. That might be more than, less than, or equivalent/equal to the cost to cure.