I did my vehicle check a few weeks ago. I think it was like $150 + taxes. Basically they'll just go over a bunch of things on their checklist to ensure everything is in good order. No problems found under my 4.8.

If you take a look at this youtube video, you should be able to reset it yourself.

BMW Oil Service Reset, Spark Plug Reset, Brake Pad Reset, Service Reset X5 E70 - YouTube