You need the fresh water tank full and the black and grey empty. Should be full of fuel (or close). If possible have a driver and co-pilot on board but you can do that add-on math later if necessary. If you have a large propane tank (the 100# kind) that should be full as well. If you are not full time you will have to estimate some of the other weights like clothing, food in fridge and pantry and other kitchen devices and utilities.
If you happen to be near somewhere that 4 point (or 6 point w/ tag axle) this is far better as one tire can be carrying several hundred pounds than opposite tire on the same axle. It that's not available then take it to a CAT scale and they will give you all axle weights for around $12.00. You can use that as a starting point, add weight to that total to make up for the missing person and/or belongings and then use the TOYO website to adjust the tire pressure. 110# in all tires is NOT correct but will do no harm either. Once you lighten the pressure where possible the ride will improve substantially.