negotiation for road bike

Went to a great shop and guy was soo nice, no pressure. Trek dealer and I like the bikes so far. Discovered I *need* a WSD, as my leg/torso ratio simply too high for a guy's bike.

My price point puts me at (all WSD) between the $1249 2.1 and the $2099 (but have seen some for $1999) Madone 4.5 Treks. They will finance. Both are 2010 Trek's. 2 issues:

Any opinions on which bike is better? This is my first road bike, need it for a 30k tri portion in May, but also have done 100k's in bike-only races.

And .... guy said to go home, do web research, and come up with an offer. That it's like buying a car. He said he'll take it if it can cover his overhead. And was helpful abt doing a good fit, getting clipped, etc.

How much would I offer given those MSRP's??

Given your price point, and the fact that you already have a LBS that's willing to bargain, I would go for the higher end bike. That being said, the fit, pedals, shoes, stem, etc., should all be talked about. Good luck and post pictures of he new steed!