fyi as a 250 owner I got an advertisement in the mail regarding $250 off the purchase of a new 500. I never actually read it (interested in the 600 myself), but if it is like the 250 'deal' last year it means if you put down $250 they'll match it with $250, so you essentially get that much off automatically.
It's not a lot, but means you should be able to get it down at least that much by haggling. Also worth checking is what the estimated first service cost for the 500 will be -- On my 250, it was a $500+ job (checking and potentially re-shimming valves), so I had them throw it in as well. They thought they were just adding a $20 oil change, and weren't very happy with sales when I bought the bike in a few months later lol.