If your willing to do the work go for it.  I would still try and get it for $800, especially if you can't get it started.  Its no "hop on and ride" thats for sure so if you are not a tinker you may want to pass because paying someone to do all that work is probably going to end up costing you more than you can sell it for.

Saw the pics. If you haven't got it running yet, then factor in another carb, cuz I would be thinking a carb with the corrosion level evident in the pics you posted will need to be changed. You are looking at not just corrosion either, but there's rust evident as well, which you aren't merely polishing out.

 If you get it running with the existing carb, then MAYBE its a good deal, otherwise, no.  Another factor to consider, my 17 year old son is talking about riding someday, and I would NEVER let him ride a bike in this shape for a first ride. A car maybe, but not a bike. So for you to let your newbie girlfriend ride it, IDK, you are taking a big risk to save a few dollars iMHO.