One thing to consider is that while the alternator may only put out 750w, current will also be drawn from the battery.
Personally, I don't do inverters in vehicles anymore after some bad experiences.
A cheap genset can recharge a battery bank pretty quickly. Couple the battery bank with an inverter/charger, and you don't have those high vehicle repair bills.
/johnny
Harris has an upcoming interview on that very topic - he was challenged, went out and did the research and testing, then will present his results.
I’m kinda psyched about it. I’ve been wanting to set up the battery bank backup system at the house for a while.
I’ll listen for his recs on battery suppliers, but I think the Costco golfcart batteries are going to be the best bang for the buck.