Question for the LJ hive mind....

So I've decided to sell my 13' round straight walled Tentsmith's pavilion made from Sunforger flame resistant canvas. Its been used 3 times, has mud flaps, a floor cloth and comes with all poles, stakes, ropes, all you'd need for a set up.
It looks like this,




Anyone have a good idea on how much I should ask for? Having never sold a tent before I haven't a clue how much to deduct for one season's use.

Anybody? Bueller?