Check the obvious, paintwork and give the alloys a close look, I noticed when picking the wife's Arona up another pre delivered Arona had damage to one of the front alloys. Most importantly with Seat or any new car in Volkswagen group make sure all the standard equipment and optional extras are fitted. Our Arona had the folding mirrors missing which the dealer knew nothing about as Seat don't inform the dealers and it was the same with out new Polo GTi which had half the winter pack missing. My advice is make a list of what should be on before you go and tick them off when you go over yours, sounds stupid but unfortunately you have to do this at the moment.
Fully agree with Cadwest above. Check the car against the specifications in force when you ordered it. If there is a discrepancy, and you do not feel it's in you favour then make your feelings known and look for some form of compensation, either in kind or an amount of financial recompense. I hope all goes well for you - I've got at least another 6 weeks to wait before mine arrives.
- Take lots of pics!
- Check the delivery mileage if you are on a finance/lease as you don't want this to count towards your mileage (mine was delivered with 112 mile son the clock).
- Have good luck at upholstery, seams, etc
As above but do try and enjoy the experience. The most important thing is the bodywork, wheels and interior condition. As soon as you leave the showroom, it's their word against yours on this stuff. Options missing is black and white so don't worry too much about this, you can bring this up at a later date.