It all depends on how much the dealer needs the sale.
I bought a V-Rod in May 2011 for 12.5K OTD with a trade. This October I went back to the same dealer for an 2013 Ultra Limited. I went on a Saturday, went back and forth on price, did not come to a deal I walked out. I wanted to trade my V-Rod, owed 9.2K, 7 year warranty, and an OTD price 24.4K. They at first offered 27K, then came back with 26.5K, I walked out. They called me on Monday morning and offered 25.5K OTD. I took it.
Here is my deal: Selling price 25.7K, trade 12.5K, total selling price 13,2K, Lien payoff 9.2K, dealer setup 1K, tax .4K, total price 24K, extended warranty 1.1K, total purchase price 25.5K.