Wholesaling - home with more sq ft than tax records show.

[Brian Haley]

I have a motivated seller of a distressed home that has about 650 sq ft more than the tax records show. In other words, he built on to the back of the home (not visible from the road) and apparently did not get building permits and has been paying the property taxes on the original floor plan before the addition. In other words, he has evaded paying taxes due. 

What are the ramifications of the sale when the county inevitably finds out this house is actually more sq ft and never reported?

Obviously, the home could be sold as the old sq ft and the investor/buyer can just go and permit it for the increased sq ft,  but I would think that the county automatically will go and assess the home as soon as it changes hands since this the county has probably seen this before. Can the county go after the buyer for back taxes? Can they hold up permits, etc. ?

If anyone can shed some light here would be appreciated.