I have a 2005 w/Ultegra and I think you would be hard pressed to find a 2004 new for less than 1900 currently. I was able to ride a friend's and ended up getting the 2005 for a little less than that from an authorized dealer in another state. What you paid for it, deal or not, is immaterial. What you get will be determined only by supply and demand and if there are any compelling reasons that someone might buy from you instead. If you are just trying to sell because it is too large/small or you just aren't riding as much as you thought you would, depending on where you are located, your advantage might be that there aren't that many places in your area where someone could see or ride one. As someone else suggested, you might have to sell for somewhere around half, but selling is all about making a connection with the right buyer, i.e., the one who values what you have to sell and your ability to sell it. Would I have been willing to pay $3-500 less than I eventually paid for a used bike? Maybe, but not sight unseen on the word of an anonymous seller - especially considering the Lifetime Warranty is only good for the original purchaser. On the other hand, if you have your sales receipt and didn't register the bike...

There are obviously a lot of variables that will add/subtract value from your offering. Another thing that might be to your advantage is to go somewhere like Craig's List for your city or some local Triathlete/cyclist sell boards where "serious" buyers would be able to see the bike/talk to you - again, not knowing why you're selling or how you present yourself, may or may not be an advantage. Good luck.