Don't have much experience but I would say no to anything with structural issues. Not that you cant get a quote to repair it and adjust the price for it. More because it could likely turn more expensive than expected and I dont have the money to take that risk. Second would be if its a bad neighborhood. I dont mind a location thats not great but dont want a place thats has too much crime and drug addicts walking around. Like one said, cosmetic, new roof, new furnace or the likes you just account for in your offer.