Backstory: I fly every 3-4 months and hate coordinating an oil change. I was on a trip this past weekend and my truck is overdue for an oil change. It hit me that I could "kill two birds with one stone" by having someone change my oil while I'm away.
The Idea: Prepay for an oil change while your car is sitting in the parking lot at the airport.
Deep Dive: You could eventually offer more services, I think those 3rd party satellite lots could team with a repair shop. You could drop off your car, catch the shuttle to the airport and have service done on your car while you're away.
Validation: I'm surprised this is not done yet, there must be some logistical issues. I think there is definitely a market for it, I would pay!
Monetization: You could charge a premium as there are no other offers and the convenience is worth extra money.