Demo/Loaner Mileage on lease signing

First time poster, great site - newbee question

If a demo/loaner car has 5K miles and i sign a lease for 36months/12K miles per year lease, at the end of the lease the car should have 36K miles (i get to drive 31K miles) or 41K miles ( i get 36K miles)?

You get to drive the 36k

Depends on the brand. Which Chevys, I believe you only get to drive 31k (so ODO is at 36k).

Mercedes loaner <20cha>

Then as @coolryans said, you get to drive the 36k. They account for the miles by adjusting the RV.

Thanks Jon & Coolryans !