Car looks great from these photos. I personally would question the paint more before buying something without seeing it first hand...unless you plan on repainting it. The paint (and body) is usually the biggest slice of your budget on any restoration. It sounds like you live in a hot climate and this is a black car, which means it will attract heat and show wear sooner than a light colored car. Questions I'd ask are: How much did he pay for the paint job? Can he fax a receipt (if so, call the shop who did the work)? Is it a ready-to-shoot paint or 2 component paint? How many coats of paint (primer, color, clear)?
It took me a few months to finally pull the trigger and buy mine. I was on this site a lot and visited a lot of Firebirds...none of the sellers were nearly as knowledgeable as the guys here. There's a ton of Firebirds available. I counted thirty-four 1967 and 1968 FB's on Ebay...probably more on CL too!
1967 FB 400 4-speed A/C Tyrol Blue w/ Dark Blue 1967 GTO 400 AT A/C Gulf Turquoise w/ Black (dad's 1st car, my last car)