Our 400w MSW inverter cost less than $75. The 23" TV and BluRay player average less than 120w. Everything else we use dry camping runs on 12v or propane. No microwave, no coffeepot unless the generator is running.
Our single group 27 battery gets us through 24 hours unless the furnace blower is going.
Mount the inverter as close to the battery as you can without putting it in the battery compartment, then run the 120v where you need it. Voltage drop is too much a problem in a long 12v feed. When I tried our little inverter plugged into the Winegard 12v socket it would not light even a 40w bulb.
