I dont think the valves have to be done at 600 for an m900. You will probably just need the standard 600 mile service- oil change, check connections, yadda yadda yadda. I think it ran me just shy off $300 up here in MPLS. Just look at the typical points that the bike would have gone down on- bar ends, dent in tank, scrapes on pipes. Check to make sure there is oil in it... I guess the normal stuff, you have been riding so you should be a good judge of it.