A good place to start is a detailed description.
Include things like wheelbase,
How far the engine is out (center of rear axle to mid plate)
How wide the chassis is in the driver compartment.
Set up for what engine?
Rearend brand and gear ratio. Wheel and tires sizes are helpful.
How old it is and include chassis updates.
Is it currently certified.
Also list things like what extra's are included. Headers, firesuit and even what shifter it has.
If you can't load pictures, include your cell phone number. Everyone has a cell phone to receive pictures.
And of course how much $$$
Matt