The QC at the factory should be thorough, so maybe just look for any transportation scrapes they have tried to cover up. If you discover any then refuse the handover until its professionally remedied.
Well, it's not realistic that you do a thorough check in a few minutes. At most you can check paint, panel alignment and very visible damages to interior. But it's not a mission, is happy new car day.
But, in the contract there's a list of all the equipment. In the following days start testing and make sure all the equipment on the list works. Don't know the level of equipment but there should be lots of drawers, seats that move a lot, and maybe even a motorized roof.
If I remember well, the only mandatory thing is the reflective triangle. Safety vests are not mandatory but recommended in CH. I know I should get one because France, but..not yet. They gave me a parking wheel sponsored by an insurance company. I got a huge and ugly CH sticker required while driving in the EU. I gave this to a friend and got a CH magnet that can be placed and removed at will.
But, I don't know the specs of your car. Does it has a spare wheel or just a bottle of tire sealant + an air pump?
every dealer is different, so dont buy anything until you have the car. A nice gesture of the dealer is also to include the Vignette for the Autobahn, but again not 'mandatory', often they also fill the tank. Sometimes you get a future car wash for free (to lure you in to get the service done there), etc.
As you see there are so many things they can or cant add... just wait and see and enjoy the moment.
I refused to sign a contract with a well know German brand for a top of the range model because they insisted on this Chf 500.-- delivery charge. It was for cleaning the car, a vignette & a tank of fuel.
I told them if i was buying a new car it should be clean and it wasn't clean this wouldn't be acceptable. The guy insisted on his "delivery charge" so i tore up the contract and left returning a few days later to fill up with fuel in a competitors' top of the range model.
Check the oil at every other tanking for the first 1K. New engines sometimes lose a bit. Dealer should give you an extra liter. Before guarantee is up check for defects, making sure that everything works. Good test is to go on the Autobahn in Germany. Check for any rattles.
I don't actually suggest you do this but I did get the salesman to read out the VIN number from the contract so I could simultaneously check it against the car I was collecting. The distrust it implied seemed to disturb him. I'd definitely do it more discretely in the future.