Does my car need to be dealer serviced to maintain full service history and warranty?

I have a 2016 Audi A3 sportback S-line. Very pleased with it, but it's now due its first service. Do I need to go through Audi? I have an excellent local garage who will inevitably undercut the prices Audi will charge. Will not getting it serviced affect resale value and the warranty? Should I just suck it up and pay through the nose to Audi?
Of course it will. Audi dealers will not take it in part-exchange. You will miss any technical service updates that would routinely be carried out during the course of an (expensive) Audi service. And, to remain under warranty, you would need to prove by a very detailed invoice that the service was carried out precisely to Audi standards using the correct fluids, parts and filters. You have paid well over the odds to get an Audi (rather than a Golf or a Leon or an Octavia), and now you are seeking to save money on servicing. "Excellent local garages" are for cars well out of manufacturer warranty. That's what they do best.
Answered by Honest John on

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