Check the wheel nuts. When mine arrived, while not loose, they were not tight either. Tyre pressures were slightly low as well.
Check the emergency kit under the drivers seat to ensure that everything shown in the manual is present.
Check that the spare wheel hasn't been nicked in transit (not unheard of with vans)
Mine didn't have much adblue in it upon delivery and took about 14 litres.
If you have ordered the tow bar it will come with 13 pin electrics so you may need an adaptor if you normally use 7 pin.
Measure the height so you will know if it will go into car parks. Where I live there are several car parks at 1.9 m headroom. When I measured my car it was a smidge under 1.89m at its highest so will just about go in. The highest point seems to be the hinges on the rear tailgate. I measured the cars height by laying a thin wood batten across the roof at various places and measured to the ground from where the batten overhangs the side of the car.
I also checked all the fluids under the bonnet. The bonnet needs to be slammed quite hard to secure it.