I don't think Diane was suggesting that the common address determines the property on which the lien is filed - only that it should have raised a red flag taken with the other factors:  The seller also owns the property with the address shown on the document, the timing of the filings, etc.  Not being familiar with how the information is presented in PA, I supposed a more observant abstractor would have identified the error.

I agree with Kevin and Robert, though. It is essential to obtain copies.  Among other reasons, many a forgery has been discovered through a simple comparison of signatures with those on previously filed documents..