Thanks guys, I really appreciate the help!
We can't camp because I require 2 pieces of oxygen equipment at night. It sure puts a damper on things.
Otherwise we would probably try to do the RV/camping thing. We're going to have to find a room somewhere, even if it means driving an hour and a half each way. Since we're making this journey, we're going to spend 3 days on the salt with all of you (Sat, Sun, Mon) then take the rest of the week to fulfill two other dreams at the same time-- for him to see the Grand Canyon for the first time, and to see a section of Route 66 as well. He never thought he'd be able to see those three things and to do them on the same trip! Holy Cow! So, I've got to find a solution other than driving an RV and camping.
Now I've gotten very worried about taking our rental car on the salt. Can someone tell me if it's possible to get it cleaned off enough that we can return it the next week without taking heavy fines? I've seen several mentions of parking at Lands End and paying someone to drive us to the racing and back. Would that be a better answer for us with a rental car? And if so, where would I start to beg, borrow, steal, or bribe someone to help us do that? Or am I worrying over-much with the knowledge that we'll only be on the salt for 2 or 3 days and will have the car for another week to repeatedly run it through a car wash?
Many thanks for taking the time to help me. I've seen already how willing everyone is to embrace those of us who are new and it speaks volumns about the true spirit of this hobby!