It seems most of the posts here are concerning larger systems for full-size RV's, 5th Wheels, etc., so I'll throw this out there.
Best $900 I've spent on my Lance 815 was replacing the original Norcold 3-way refrigerator with a Vitrifrigo Danfoss type compressor fridge a few years ago. I've measured daily energy usage on the unit at between 280-340Wh, depending on ambient temps and how often I'm in it. Measuring the 12V load pulled by the older Norcold unit showed 10x that energy usage.
With the 100Ah LiFePO4 I've had in the rig until about 3 weeks ago (now have DIY 280Ah installed) and between 200w-400w solar panels active at any given time (2x100W on rig and 2x100W portable), I never have to worry about power, even during extended cloudy/rainy day periods. I also gained over a cubic foot of capacity and no longer have to worry about parking on a non-level site at times. I have a real freezer section and I know I'm not going to have to either shut off the propane or worry about the burner getting blown out by crosswinds or passing vehicles.
When I take the camper off the truck when I'm at home, I leave the fridge run with basic items in it and I'm ready to go. No need to plug into shore power unless over the Winter when I run a small space heater on the coldest nights. The two 100W fixed solar provides more than adequate power to make up for fridge use and parasitic loads even when I've had a week or more of overcast/rain.
I originally added solar and the LiFePO4 battery in an attempt to make the 3-way fridge more useable for off-grid...use propane at night and 12VDC/solar during the day. With 4 panels active on mostly sunny days, I could run the fridge all day and charge the batteries to make up for nighttime power usage for lighting, recharging or running a fairly high-powered laptop for photo/video editing. My rig only has one 20lb propane tank and if I used it for the fridge full-time, cooking, hot water heating and occasionally the furnace, I was only good for a 10 days to 2 weeks, sometimes less if really cold weather. Not good!
Cost of the original solar setup was: $1640 consisting of...
4 x 100W Renogy Eclipse Panels $170 ea - $680.
1 Renogy Rover 40A MPPT Controller $160
1 Battleborn 100AH LiFePO4 battery $800
I could have saved quite a bit on cheaper panels, but I liked the small size of the Eclipse panels and have been very pleased with their performance. The Battleborn battery has now been replaced with the DIY 280Ah unit I put together, but it still tests out at 102Ah after almost 4 years of usage, so I'll repurpose it or maybe sell it. With the larger capacity battery that I have in the rig now, I leave the truck/camper 12V interconnect open...never bother charging from the truck when driving, just let the solar keep it topped off as I drive.
Bottom line, it all just works...and no worries about having enough power or charging/discharging profiles being adhered to with FLA or AGM batteries.
Cheers!