All belts, filters, and fluids should be REPLACED. You need to know what you are starting with and the best way is to start fresh!
Batteries, what is their age and what is their electrolyte status - check with a hydrometer, then make sure they are filled.
Tires - how old are they? If older than 7 years replace. Otherwise, make sure they are filled to the proper amount based upon the weight of your coach. You have had it weighed, right? If not, that's another To-Do for your list.
Wait until you've driven it a little bit to see what the shocks/sway-bar feel like.
Check your electrical cord for any sign of discoloration. Check water hose for leakage around fittings. Check waste hoses to any pinholdes.
You do have a multimeter, correct? If not, get one.
Toilet, does the bowl hold water. If not, think about getting the dump seal replace.
Water pump, does it easily move water around and shut off when you close the faucet. If it keeps going, you've got a small leak somewhere.
That should get you started.
The battery I purchased has a charge voltage of 14.6
I think I'll look into buying a charge controller that is definitely for a LiFePO4 battery, The PWM controller I currently own does have a lithium option but it doesn't specify LiFePO4. So I'd have to gamble on it being compatible with LiFePO4 batteries, and I'm not willing to gamble.
For western Kansas, Lake Scott State Park. Just south of KC/Olathe is Hillsdale State Park. They should be reopening after the 4th. We should be at Hillsdale before the Rally. Ooops! I have to get signed up!!