By the way, $15 K sounds a bit steep for a 99 is it a hardtop or a ragtop? What is the mileage? Has it ever seen rain or snow? This would also be helpful in getting your price. You can also check out
www.edmunds.com to get a fair market value for your 99 GT that you're looking at. Make sure you input all of the options, the mileage and the condition and it wil give you a price. Hope this helps.