I am a new owner - this is my first post. Just bought a RTL/SR for invoice last week in Iowa. The truck already had rear mud guards ($92) and paint sealant ($345) on it. I did NOT pay for those items and they were not included in the invoice. (I would have ordered the mudguards, so they screwed up by adding them as soon as they received the vehicle.)
There was one little hiccup in the deal. I had told the salesman I would pay only invoice and he knew I was serious. He made a couple of quick trips to the "back office" and ultimately showed me a price that was the same I had confirmed as invoice on an RTL/SR and we agreed we had a deal. I gave him $500 and we made an appointment for me to pick up the truck in two days. We were a little rushed, as it was just past closing time for the dealership and he seemed anxious to go. It wasn't until I was my car that I remembered the infamous "document fee" - we hadn't discussed it. Sure enough, when I went to pick up the truck, there was a $185 "administrative fee" on the paperwork. I just said I wouldn't pay it and the clerk said "OK, just give me a moment to redo the paperwork." The last car I bought (different dealer) only had a $25 fee - I didn't pay that one either. Some dealers may be tougher on this aspect.
I lurked at this site for a couple of nights before I went to buy. It is an outstanding resource. I will be returning for more info on accessories (esp. a bed cover) and to follow others experiences living long term with the RL.
I don't believe that it is necessary to pay more than invoice at this time, though that might change soon. (Will the dealer incentive be gone Sept. 1?)
My truck had 5 miles - now 145. Love it so far. The bed is still virgin. Mostly, I have been running short errands and listening to the "40's" o the XM radio. (In fact, it might as well not have any other stations!)