For class A’s whether diesel or gas I would recommend looking at, Newmar, Tiffin or Winnebago. Those 3 have good quality relative to others, in general, and all 3 make several class A with many floor plan options. As I said in my first post to you..make sure you have a qualified person inspect...I have seen what can happen if no inspection is done.
You can get very good gas or diesel units..some people will tell you “have to get gas some say diesel” you can get good performance from either..gas units are typically cheaper..
We tow a 2017 Jeep Cherokee Trailhawk behind ours..we tow 4 down....when towing read your owners manual and find out how your car/truck can be towed..some (actually most) can’t be towed four down and some can’t be towed any way other than on a trailer with all four wheels on the trailer. It is amazing how much damage can be done if it is not towed properly....
If you have any questions let me know and I will be glad to answer...
I think my preference, if you’re towing a car, is diesel. You don’t lose much mileage if you’re towing with a diesel.