I too will recommend the Honda or Yahama inverter units, a 3500 should be about the right size (Let's see 3500*0.8 = 2800 watts of continuous power bit more for motor starting).
These are quiet, SIP gasoline (Many of he HONDA's can be used with an extended run tank so you can run them a long long time if power fails)
In addition you might consider a pair of 2000's.. More power, when parallel hookups are used, and each unit is easier to wrangle.. .Kind of like why they use six volt pairs instead of 12's in many motor homes.. half the weight per box.