Hi Haze2,
The walk through will be good and thorough if you insist on it being so. Some dealers will do things right. Some need help. If they need help, dispense it politely but liberally. You might want to have one person follow along and have the other one taking a series of videos. There's a lot to remember. Video will help.
It's a good idea to stay at or near the dealership for a day or two after taking delivery, before your long trip.
Before signing the papers, talk to the Service Manager and arrange that if you find anything that needs to be adjusted or fixed during that day or two, that he'll have it fixed immediately while you wait. That conversation can include the sale and finance people, but you must have the Service Manager's agreement.
Of course if something needs to be repaired where parts have to be ordered, you'll have to make a decision about how to manage that. You might have to pay to have parts shipped overnight delivery. Or you could drop the trailer and pop up to Elkhart and back in one day to pick up parts and have them installed the next day.
Not saying that will happen. But you should allow time to get things right just in case.