We found a new RV but had to wait a few weeks for delivery and some modifications. We were offered trade for the old one, and were willing to go that route to save money on taxes and for the ease of getting rid of it. While we were waiting for delivery we took the chance of listing the old one on RV Trader and wound up about $5000 ahead selling it outright.
We knew our break even number for trade value and tax benefit, and made that our bottom line in selling it ourselves.
Of course if you still owe money on the old one, that makes trading it much easier.