I have my 18k mi service coming up next month (you can probably imagine how much I love riding this bike

), so I have a few questions...hopefully you guys can guide me...
1. I heard that the 18k service is a major one and requires valve adjustment too. What is the approximate cost for this service?
2. I usually change the oil and oil filter myself. Do I need to get the service done by the dealer (without having them change the oil and oil filter) and later change the oil+oil filter myself? ...or shall I change the oil+oil filter and then take the bike to the dealer for valve adjustment?
3. What else is done as part of 18k service?