mine just out of warranty from new and I have done all the service myself since
actually just changed the diff oil earlier today
.....i think as long as you keep the reciepts of the parts and document the service work it should be fine .
As dealers sometime don't do as good a job as you would on the car .
but if your not good with a spanner ...you have no choice , but take it to a "good" specailist, as Bmw will be twice as much cost wise (as listed above )!!
oh re resale values...of cause its better with a Full bmw history , but if you document the work done by your self or a Indie specialist , the hit in resale will be less.
I personally never buy a car on service history alone ....rather on the condition of the car and work carried out is more important .