Carson makes a small one that is pretty light, but with little amenities.
Exactly...it all depends on what you want out of it....if only a place to sleep, haul your shizzle then you don't need a lot of amenities. You'll usually get a queen size bed and a couple bunks minimum...Think about how many bikes you're going to haul and figure out the footprint of cargo space you'll need. I have a 29 ftr with 12' of cargo space due to carrying a buggy (no more)...if I carried only quads I'd still need the room, bikes don't take up as much room. roughly 2+ bikes for every quad...
If you get one in the teens (length you MIGHT be able to drag it with your Donkey...not recommended though!