Should I Buy this mustang gt

Well 157K is a lot of miles...can't say what might need replaced just looking at pictures. You'll have to go check it out and see. $4K isn't too bad though, looks like it will need some cosmetic work inside and outside.

I'd be wondering if the plugs have been replaced, '06 had the 2 piece plugs that are known to break off in the head when you try to replace them, but Lisle makes a tool to remove them if they do break. They should have been replaced by 100K but who knows if they actually have.