I suppose reading this thread is actually quite interesting in regards of what servicing actually means to a potential buyer.
Im in the motor trade so picked up my E39 M5 as a bit of cheap fun and something to either use when i had to travel a long journey(200miles+) or to blast around track days and go the ring in.
ill do all my own servicing and replace whatever needs doing myself as for a 11yr old vehicle i feel its silly to pay BMW lots of money for something you can easily and cheaply do yourself.
Do i feel that it means the vehicle is going to be worth nothing, well not really as these are so cheap nowadays that if i spent £3000 on bmw servicing and parts(assuming through the years i own it) would i be able to put that amount on top of the value of the vehicle when i came to sell........i dont believe i can.
I suppose im in the same position as the OP really, I didnt lust and love an M Car before i bought this, just came across it in the trade and decided to try it out.
I wouldnt say its an amazing car, but its a nice car to drive and ill be able to fit a baby chair in the back come january etc.
maybe the OP is in the same position, by one cheap, look after it himself and enjoy it, I would treat is as any other car really, change the fluids every so often and dont abuse it when cold and im sure it will be good to you.
I think maybe because its an M Car it needs to be put on a pedestal and loved and cherished, but at the price they are now i dont think they warrant that, if it was a few years old maybe, but not a decade+