Hi and welcomr to the forums.
There's about a bazillion threads on this and they express a bazillion opinions.
If you only need to recharge the coach batteries a Honda eu100 has you covered. Light and cheap.
If you want to run A/C, Microwave, refrig etc all at the same time most folks opt for 2 eu2000's in parallel. eu2000's are still light and easy to move around.
If you want to just run the A/C or Microwave. A Honda eu3000 will do the job but it weighs 180 lbs.
The thing the majority of Members agree on is. Use Honda or Yamaha gensets.
Both are very reliable with a long use life and also of importance they are very quiet. Thus you and your neighbors are not irritated by the racket of a discount genset.
Hope that helps.