I'd get him to back down on the price some, and then contact an independent shop with a good reputation to quote you their price on doing the required maintenance. My 07 has 40K miles on it, still on the original brakes, although I'll likely have those replaced in the next few months. I still use the dealer for oil changes, and that runs me under $90 with BMW CCA discount. If the car hasn't been abused (doesn't sound like it has) and you treat it well, it should be a great car to enjoy for several years.
And yes, you can take it to the dealer (or a good Indy shop) and get it inspected, but prices will vary.
2013 F30 335i M-Sport 8AT/MPE/MPPK, 2011 128i M-sport Cabrio 6MT/PE