Is it a good idea to get a family friend to service an Audi?

We are looking at purchasing a 2005 55-plate Audi A4 Avant 2.0T FSI S-Line. It has done 77,000 miles. My dad (an avid follower of Honest John) says that we are silly as we wouldn't be able to afford even an oil change. Please can you tell me whether parts and servicing etc are expensive or whether this is something that was true years ago but not so much now. We have a family friend who would service it for us so it wouldn't necessary be with an Audi garage.
Parts and servicing are expensive and "a family friend" will not have the diagnostic interrogator necessary to do the job properly.
Answered by Honest John on

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