Timing guides are 3 plus some sliding pieces for the tensioners $250-$300 for all.
Timing tensioners are 3, one for the main chain $48, and 2 for the secondary chains $140 both.
Some gaskets, less than $100.
Parts are $500-$600 and labor depends on the shop. Call around. This job requires BMW special tools for timing which can be bought or rented for $350? The job does not require front end of the car to come down, but radiator, alternator, steering pump, water pump assembly, valve covers, all 3 timing covers...
JOY = BMW