You can save a boatload of money buying private party used. You need to check the unit out well before you buy it, but there are a lot of really good trailers and fifth wheels out there that have had all the kinks worked out and have been well cared for.
Another reason to consider used is it makes it easier to buy outright, which may be important if you find your tow vehicle insufficient and find yourself looking to upgrade that sooner rather than later.
The other great thing about buying used is you're not taking that depreciation hit, so if you find the trailer isn't working for you for whatever reason you can turn around and resell it for what you paid provided you didn't overpay.
