Well, I'd imagine the dealers not toooo tooo far off on that. Its tougher to get a good price on a convertible in the summer than in the winter, and navi is a pretty hot option, therefore I doubt they'd move too much. I would shop around though, you never know what fringe offers a dealer will give. A friend of mine is buying a tC now, and dealers won't negotiate the price, but one has offered her a gas card, another free oil changes for life.
For more info, check out
www.solaraguy.org I think there's more ppl there then here w/ gen 2's