I have leased cars for many a year. My experience is the small print from the lease company will include something to the effect that the vehicle has to be serviced at a manufacturer main dealer. They can do this as they actually own the car and can specify where it is serviced.
Its different if you buy the car, as then you can get it serviced wherever as long as its to the manufacturers specification and use oem parts. You will maintain the warranty lime that.
I have had 3 Mercs on lease and every one had to be serviced at Merc as part of the terms of the lease.
Stuart
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