Help on Service and Warranty

You can have work done anywhere you want, even do it yourself. While I do most of the inspection work and air filters myself, I let the dealer do the fluid stuff (oil, brake, trans) so I don't have to dispose of the used fluids.
While I have never been asked for proof of maintenance by any dealer (Acura, BMW, Lexus or Mercedes), I do keep my receipts (just in case). For any work you do yourself, you can just keep the parts receipts.
Since your friend works at the dealership, I don't think they would appreciate him moonlighting, so you may just say it was done at an independent shop if anyone asks.
If a warranty company wants to deny a claim due to lack of maintenance, they basically have to prove that the lack of maintenance caused the issue. So unless there is something glaringly wrong you're not likely to get questioned by the dealer.



