I think you should do it your self and save $250. all you need to replace is the oil, oil filter, and clean the chain. Use 10-W40 (3 qt's) synthetic 4 stroke motor oil.. I prefer the racing 4T oil from Mobil 1. You can pick up a filter from the dealer or I think Walmart for around 10 dollars... to clean your chain use #2 diesel from the pump, and motul chain oil after its clean, you could also use Maxima chain wax.. my partner swears by it.
Make sure the idle is around 1400ish, and if not you can adjust it. the screw is about knee level on the left side.
throttle play, it should feel smooth and does not stick.. if it does its an easy fix.
break pads should look like they have a lot of meat on them for 600 miles
Should be able to move the handle bats and the wheel moves with them, if there is any play between them.. thats a big problem
In all it should cost you about $65 for all the parts and oil, and a lot of TLC time with your girl
90% of all the parts could be bought at cycle gear or your local cycle shop.