My "house battery" is back in the car under the door that supports the refrigerator...
My positive output goes to a circuit breaker
(70A until my 135A replacement arrives), then to a fuse panel that sends output to both ham radios, a refrigerator, and the car's factory 12V outlets
(to be powered by the LiFePo4 instead of the starter battery). The 12V outlets currently power a Raspberry Pi3, GMRS radio, WeBoost cellular booster, and various chargers. Also shown in the photo is a Victron 30-amp DC-DC smart charger, a remote temperature sensor
(white box next to the charger), three of six cooling fans, and one of two thermal controllers for the fans. It would be very easy to power the 400-watt pure sine wave with the LiFePo4, too. For now, I choose to run the inverter only when the engine is running. I've also left room in my setup to eventually add a 500-watt HF amplifier, which pulls 80 amps on transmit. This battery and BMS can handle 130 amps for 30-45 minutes before depletion.
I'll remove it again tomorrow to clean up some wiring, top-balance the cells, reinstall, then I'll be done.