First off, you need to know what exacltly are you buying....
Is it a Firebird? Firebird SE? or Trans AM.
Then you need to know if its a 2.5 (4 Cilinder) 2.8(V6) or 5.0(V8)
Next, what is the miliage on the motor?
Make sure you also check for the following things:
Light motors flip up the lights at the same rate (if not one is going bad)
The wires in the engine bay are not all taped with black electrical tape.
The color of the engine bay, as opposed to the car (mabey a wreak re-paint)
The sound the clutch makes (if 5 Speed)
The idle should be set at 650-700.
In the trunk where the spare tire is, (right side) make sure there is no rust
When car is cold. Start it, make sure there is not alot of smoke coming out
Look at rear right tire to check if the guy has been riding it hard.
Also look at the others, in case he swaped tiers.
Check VIN number for authenticity of motor, etc. Clean title.
I am only probably gonna post once here and not look back, so if you want to ask anything else, feel free to email me. MarcinLobrow@hotmail.com