You may or may not need to clay a new car, depends on how and how much it travelled to get to you. My first car came from California to Ontario, Canada, and was part of an inter dealer trade, so it was highway driven for a few more hundred kilometres. It needed to be clayed and detailed very badly. My focus was built just 2 hours away and had a dozen miles on the clock when I picked it up and did not need to be clay barred.
I drag my fingers across the paint. If it feels like perfectly smooth glass, it does not need to be clay barred, but if you can feel imperfections, it could probably use it.