In general. If you want to run everything, 2 AC units micro etc simultaneously, 5500 watts.
If you can get by on those trips with one AC, and an occasional coffeepot, microwave etc, a 3500 watt unit should suffice
If you want to brew a cup of coffee in the mornings, and keep your batteries topped off, a 2000 watt unit can work.
Open frame construction genny's no matter the brand are louder and bring more derision from the purist.
Inverter genny's no matter the brand are quieter.
Cost , no matter the type will follow a pattern
Most expensive portable to least,,,,
Honda
Yamaha
Champion
Predator
All the other chinese made genny's with honda clone engines.
Now
Let the battles begin.