Depreciation of Home Resale from Oil Canning

Hi. I've posted here about the horribly oil canned metal roof. The builder finally got back with me after talking to the metal company rep and the roofer. We talked about doing a more narrow panel with ribs in it. So he says "we're trying to come up with a price for you". Obviously this means they aren't footing the bill for a new roof. They may give us the upgrade credit back (9k). My question concerns the depreciation of the house if we were to sell it. If I saw a fairly new house like that, I wouldn't want to pay top dollar. I need help coming up with a number! Thanks!

If the roof isn't improperly done (i.e. alignment, tie in, flashings, etc.), I think the oil canning concern is somewhat subjective. It is a natural phenomena of metal just like toxic run off and granule shedding would be normal for asphalt. I don't think a home inspector could justify a depreciated value based on that fact alone to be perfectly honest. We have some client that actually want the wavier look. Go figure.