Picking up an RV can be a really big help ----if we ask the right questions and sometimes we have to "force" the sales folks to come up with answers that they may not know.
Keep in mind it is their JOB to know the product they are selling. Many want to skip over tellling us what we are buying exactly!
No need to accept answers like RV are all the same! EVERY RV may be slightly different than the next, so they should be willing and able to show you things when you ask.
I suggest going in withe right timing, so that you and the dealer should have plenty of time to do a really good walk through without rushing at 4:30 to close a 5!
Ask specifics like where and how ius the water left. Is it winterized and where are the valves. Since we all now carry a video camera on the hip, Take lots of short videos while they point out valves and switches for things.
I don't know is not an acceptable answer! Somebody around here should know and it IS their JOB, so if they expect to be paid, why not ask them to work for it?
No need to be disagreeable but then the grocer should not expect to sell you rotten meat, so why RV dealers?
On the trip, I suggest doing campgrounds with water and electric as a way to work into any questions more slowly. The motorhome wILL have numerous smallish points that can show up as something bIG, so having good electric and water can avoid many of those small points like run down battteries, etc.
Keep the owners manual handy and read lots, study lots, but try not to stress if things seem wrong. Being experienced likely will help if you want to wander around the campground to "stretch " and possibly ask a few friendly questions???
Try to arrive in daylight to sort those early setup questions.
Tons of info online from Winnebago here:
https://www.winnebago.com/
Look under the owners tab as a step into a deep well of info not provided by lots of other brands.
And the group is always standing by for the when the manual totally confuses us or slides by too quickly!
Enjoy the trek!