Good choice. The 800 is reported to be one of the best and most reliable Monster engines and it's a nice-looking bike, too.
My owner's manual also says to grease the threads on the axle and on the chain adjustment screws. Now I do remember doing that a while back. Just make sure to use a torque wrench and tighten to what the manual says. Be careful with the chain adjustment screws; it's easy to over-tighten them or break them. On the other hand, make sure to check them during your first ride after the adjustment. Because the spec on the adjustment screws is low, there's a chance they could vibrate loose. This has happened to me twice after having tires installed at shops.
Do you know how old the belts are? They should be replaced if they're more than three years old. If a belt fails, the valves will hit the pistons and that's not good. It's pretty easy to do and I've done it a few times. The only slightly tricky part is getting the tension right. I even adjust the valves myself, but once they're broken in they don't need much adjusting.
I order belts, valve cover gaskets, and other maintenance items from California Cycleworks.
http://ca-cycleworks.com