While 40% is possible, it certainly isn't likely. Even in today's market only the big, high volume dealers can afford discounts in the 25% range (assuming you are starting from a real MSRP and not a dealer's fictitious "regular price" shown on his own letterhead).
The way to get the lowest price is to hang tough - don't be afraid to say "I think I can do better" or "I'll think about it" and walk out. Your feet are your most effective bargaining tool and salesman hate to see any customer walk. They WILL call you back in most cases, sometimes 3-4 days later (make sure they have your phone, but they usually try to get that up front anyway). And don't be afraid to make a low offer or counter offer. You aren't making new friends - you are making a deal. This is like buying in a middle eastern bazaar - offers and counter offers, lots of wailing and moaning on both sides, attempts to make the other feel guilty or be embarrassed for naming such a low price. Shrug it off - this is primeval sales stuff and hang in there.
Of course, if you are uncomfortable with buying away from home, you may as well get out your check book and deal with the local guy after a few weeks or months of haggling.
We are lucky to have a mega dealer only 100 miles away, so we enjoy good purchases prices. Service is wherever we can find it. I've had excellent service while on the road, thousands of miles from home, and crappy service within 50 miles. And vice versa too. Some dealers have learned there is money to be made in service and some still seek only the sales dollars and screw the rest (including warranty customers whose bill will be paid by the manufacturer).
If you buy a higher end model, you can probably get factory service, which is usually far superior to dealers. Tiffin is one maker who does factory service for all their models, but most only do it for mid-high end.
