Since you said 1995, I believe that makes yours a 16', which originally had a small 3-way
fridge. A 3-way gives you the most flexibility for camping with and without services. Unfortunately, I don't think any manufacturer is making an absorption
fridge in that size any more, and there may not be room for a larger model. You'll have to take measurements (HxWxD) and see what's available. You might also be able to find a used salvage unit in the right size.
But since you're planning
solar and a lithium
battery, a 12V compressor fridge is well worth considering. Modern 12V compressor fridges are very efficient and hold temperatures more reliably than older absorption fridges. A small unit that fits the space shouldn't be too power hungry, and between
solar and
generator back-up, you should be able to keep up with a basic 100AH lithium
battery (200AH would be better, but you'll need to find a different mounting location). The advantage over your current 110V fridge is it will run directly from the
battery without an inverter when off-grid (which adds additional expense and inefficiencies).
Do you have a
propane furnace? Even Florida and other sun belt states can get cold enough to require nighttime heat. The
furnace also uses 12V power for the fan motor.
I don't see an older
Casita manual in the document center. You might want to order Eileen Glick's
Casita Travel Trailer A to Z Owner's Guide. It's far more thorough than the factory manual and available in print or PDF format.
We do all our cooking outside as well, divided between a Coleman stove and a Weber Lil Joe charcoal grill. We like to grill meat and veggies in the evening, and then chop and sauté leftovers in the morning with eggs for quick breakfast burritos. We've used the onboard stove once or twice for a quick heat-up in inclement weather.
It's a little farther, but AZ is another great wintering ground with plenty of public land available for free dispersed camping as long as you're set up to be self-sufficient. The area around Quartzsite is a favorite, and there's a molded
fiberglass trailer gathering there in early February. There are also some private campgrounds along the lower Colorado River, as well as very nice state and country parks scattered across the warmer parts of the state, but you'll need reservations well in advance.