Don't forget who the customer is. You have the right to ask for anything you want to see. You have the right to know what the full terms are (interest rate/length of loan/Payment). You have the right to ask to see a factory invoice. Many dealers now post those along with the pictures on their websites. This is helpful in determining what is on the trailer before they try to tell you want the other additional charges are.
If they balk at providing the above minimum information, run out of there before they screw you and find another dealership. I actually think it's easier to negotiate by email and phone than in person and it really takes a lot of the more proven tactics of some of the shady salespeople/dealers out of play.
You ask/They provide. They don't provide, You ask again telling them your still waiting on that before you can make a decision. They delay or don't provide, you just politely call and remind them again your still waiting on XYZ. They will either give you what you ask for or move on at which point, so can you to another dealer.
I had all of the above along with a Purchase agreement fully completed showing what I would be paying down, Interest rate and term in months before I ever left my home to go to the dealer that was 90 minutes away. I walked in, we went and did a PDI, I asked them to correct a few things and told them I had decided to pay cash instead of finance the $7,500 I was going to owe after my trade in/payoff of old loan. I went to the bank while they finished my requests, put a battery on it, filled the water tanks so I could do a final test of all the systems.
When I returned, we did that, I signed the paperwork, handed them the check and headed home about 4 hours after I had walked in. From my first phone call to let them know I was interested in buying a specific camper from them to me driving out of the lot owning it free and clear was a total of 5 days. About 3 of those were because I was shopping finance costs with my own lenders vs. just accepting "what they could get me" for a rate.
Good Luck in making a decision your happy with but don't be afraid to stand your ground on what you want to make sure your happy with whatever deal you make.
2020 Chevrolet 2500 LTZ, 2019 Forest River Wolfpack 23Pack15, 2014 EZGO Golf Cart.