'Delivery miles' on an F10 M5

[Carpmart]

What's the consensus on how many miles is reasonable to have on my new M5 when I collect it on Saturday?

How many miles can they really rack up, rolling it around the yard and on and off trailers/trucks?

[Carpmart]

Exactly that, that the car has 'x' miles on it, when it's supposed to be brand new. What is a reasonable number others feel 'x' can be before it's no longer reasonable?