My advice is speculative as I don't know the exact situation. You hopefully have a buyer's agent providing expert advice. Generally I think there are two problems. The first is the cost to replace the roof, the second would be how much to repair the damage caused by a bad roof, which can be expensive. If your accepted offer takes that into account, then I think you are good to go, if not I would seek a reduction in accordance with the damage, unless it was an as is sale and was priced accordingly.
Tom Brady SFR, e-Pro, SRES, GREEN
Licensed Real Estate Salesperson
Notary Public, Ret. NYPD Lt.
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Charles Rutenberg Realty, Inc.
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