sticker is a good price to pay at the begining of a model year, IMO.
500 over 'invoice' sounds like a really good deal to me if you can find out the true invoice - that won't happen at the dealership.
Later in the model year when you can find dealers eager to get rid of them 15 to 17 thousand is evidently a possibility.
Wow, if you can get an '04 Insight for $500 over invoice, that would be a very good price at this time of the year.
As far as I know, at least in metro-ATL, the Honda dealers will only order 2004 Insights if the customer puts down a non-refundable deposit. In other words, there will be pretty much no room to bargain. Only if someone orders one, changes their mind and a dealer gets stuck with one, will there be any sort of a discount.