Should one assume that the item is not in your possession?
If not, I would be hesitant to list it for a number of reasons.
1. Hard to describe an item you cannot see.
2. Stock Photos will cause issues way too often.
3. Shipping and Handleing Delays.. A friend sold a car for a third party. Buyer traveled 200 miles to pick it up. Sale came undone as owner "just didn't have time" to drop off the title.
Lastly, I would never allow the owner to "fulfill" the deal on their own. It's my reputation at risk.
Good Luck