I've had mine since middle of November and we're about to service it for the second time... so that's already twice in 6 months, mind you we got it brand new in November 63 plate, and it's on 23,000mls
63 plate Berlingo working hard.....
I've had a mark III since 2010 and it's done 305,000 miles doing courier work. I change the oil and filter every 12,500 miles (about every 8 weeks in my case lol!), and use SAE 5W/30 engine oil. Yes... I've done 24 oil and filter changes since buying the van!...it's a good job that it's a simple job on the Berlingo (if you have a pair of car ramps that is). I have a new Berlingo L2 on order with the "Look pack", and will post a pic of MY new "Work horse" when I get it.
Have you had to change the turbo during those 305,000 miles?
If not, then regular servicing seems to be the way to go to protect the turbos