Per the Allegheny County website county taxes for 2009, 2010, 2011, and 2012 have been paid. You should contact Allegheny County at 412-350-4100 and obtain written confirmation from them as this information is not guaranteed. For prior years and delinquent county taxes contact Jordan Tax Services, Inc. 412-835-5243 and for the years of 1997 and 1998 you may need to contact GLS Capital, Inc. 412-672-7200. For local and school those taxing bodies should be contacted.
It would be best to contact a good real estate attorney who is also a title insurance agent and have them conduct a title search.