So weird that they got the rest of the house apparently right by opted for cheap lumber in a support beam. There are two such beams under my place, and they are steel. Of course, my place was built back in the 30's.
Makes one wonder what other corners they cut. Is this place part of a subdivision?
I'd be concerned about drywall cracking, if I were you, as well as creaks and grounds coming from straitening the structure. Drywall is a giant pain in the ass, and expensive to have redone if your not doing the work yourself.
On the other hand, you could be able to negotiate a seriously good deal if your willing to put up with all of this.