Really not unusual for bikes on C/L to sell in a couple of hours, particularly if they are a good/decent deal. As you are looking at relatively modern bikes, you should consult bikepedia (it has almost all bikes 1993 and newer) for original pricing, build and other details. If you want a great deal, you need to be ready to pounce quickly, get in the car and drive, when a deal hits. You can beat out the folks that are studying up, pondering specifications, etc.
C/L ad does not list a price, which is in violation of C/L policy. I shy away from sellers looking for best offers, auctions are best held on ebay.
Bike is just before the conversion to STI, and it is a bonded aluminum frame, both of these are negatives in the modern bike market. Bike is probably worth about $250 in clean, ready to ride condition. Steel Treks draw a lot more interest.