My rant is based on the fact I can't seem to find an RV lot to suit my needs.
You are looking for a coach; the RV dealership is looking for a sale. Until you both come together there will be frustration on your part and also on the dealers part. They have no idea you are serious or just passing time so they try to get you to tell them how soon you plan to buy and what you are looking for. That is just good salesmanship. If they want to run your credit just say not until we pick out a coach and agree to a price. Until then give them nothing especially don't give them a deposit. For any dealership it is a numbers game; many customers will look and of that a percentage will buy. They try to figure out if you are a looker or buyer early on and that determines the time they spend with you. Asking for a deposit or a credit app is one way to determine which group you are in.
RV sales are strong so you need to tell the dealership you are serious and will purchase as soon as you find what you are looking for and at the price you will pay. If that is not enough for them to spend the requisite time with you then move one.