To keep your toilet seal in good shape, fill the bowl with water, put a couple dabs of Vasoline on the toilet rim and then stretch Saran over the toilet so the water doesn't evaporate.
Also, after you empty and flush out the black tank good, fill it about 1/4 with fresh water so the bottom doesn't dry out in case there's still some 'stuff' in there.
Give it a very good wax job and 303 on all plastics/leather.
Cover the tires but be sure and secure them tightly for any winds.
Put the silver foil material in all the windows to keep the hot sun out and close the window coverings.
We always took a mesh small laundry bag and dumped a box of mothballs in it and hung one in a couple places in the basement, including the engine area for motorhomes. This controlled pack rats for us and the mothball smell went away within a few days after tossing the bags upon return.
I don't know if they help but we also put sheets of fabric softener in all the drawers to keep mice out. It worked for us.
We stored bedding, pillows and sofa toss pillows in a Hefty bag just in case mice would come in.
Full-timed for 16 Years . . .
Traveled 8 yr in a 2004 Newmar Dutch Star 40' Diesel
& 8 yr in a 33' Travel Supreme 5th wheel