what size inverter.

Ok so building another battery and I am wondering what the smallest size inverter people would run in a camper.

I am thinking if I get a 1500 watt inverter and if I decide to put a microwave in at some point then get a smaller 700 watt one. is a 1500 watt inverter practicle for most normal stuff?

the reason I am looking at that size is that is about a 125 amp draw so I can go with a 150 amp BMS and not be running flat out.

Steve