Yes, tell us more about what you actually plan to do and how you plan to do it....Simply saying "nights under the stars" gives us very little to work from...Also, what is your experience driving large vehicles, trailers, etc? Do you have a vehicle currently that could tow?
Brand means little. Outside some extreme high end rigs, they are all put together pretty much the same way using the same pieces and parts, so don't expect brand to have much impact. Buying used, condition is everything. One suggestion is to try and find a mobile tech you trust who does inspections. Wait until you are ready to make an offer and make the offer subject to inspection. Not a perfect solution but a halfway decent tech will find issues, you won't even know to look for.