There is no one answer to your question. It really depends on what you intend to do with it.
1,000 Watts will recharge your battery if boondocking. Won't do much else; maybe run your electric shaver, fan, or radio.
2,000 Watts will also run a hair dryer, microwave, but only one of those things at a time. It will not run your air conditioner in all likelihood.
3,000 Watts will run your air conditioner; but not while doing much else.
4,000 Watts will run most everything in a reasonable way.
I only run a 2,000 Watt. If I need air, I get an electric site.
Some people really like linking 2 2,000 Watt generators. Only run the second one when needed, easier to move around 2 smaller units than one big one, and often cheaper than a 3,000 Watt unit.
And do your fellow campers a favor (as well as yourself) by getting a nice quiet unit; like Honda or Yamaha. Don't be fooled by Db noise ratings. They are not linear but are exponential. Every 3 Db approximately doubles noise pressure. So, a 79 Db sound ratings is about twice as loud as a 76 Db rating.
Take your pick. Have fun. Be safe.
2012 F150 FX4 Ecoboost, 2016 Surveyor 274BHS
2003 Yamaha FJR1300, Demco Premiere Slider
1969 John Deere 1020, 1940 Ford 9N, 1948 Ford 8N
Jonsered 535, Can of WD-40, Duct Tape
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