First, I presume you are working with a Realtor. If not, I urge you to consider enlisting the service of an experienced Realtor. Typically, there is no charge for a buyers' agent service, and the benefits are numerous. That said, prior to making an offer, you may ask the sellers (perhaps through their Realtor, if it is a listed property) if 1) They have flood insurance, and 2) have there been any insurance claims on this property. The owner can contact their insurer and get this information. I urge you to get any answers in writing. 3) The sellers disclosure, a requirement for an owner occupied home in Pa. that is listed through a licensed broker, should note any defects as they relate to flooding, water in basement, etc. This is a legal document and I urge you to review it carefully. Further, should you have any concerns about the above items, but remain interested in the property, you could consider having an attorney review all of the information you have (insurance reports, seller disclosure, contracts- prior to signing) to make certain you are protected. Finally, given all of the above, and you are satisfied with all of the information provided, and you intend to make an offer, should you enter into an Agreement, you should pay for a professional Home Inspection by a qualified individual/co. (one of a number of "contingencies"you could/should include in the agreement- speak with your Realtor or an attorney) who will carefully inspect the property and determine if there are signs of past or present water damage/infiltration. I know this is a lot of information, but take one step at a time, and you should be well protected.