I bought the cozy coupe for my younger grandson (1.5), and the older one immediately commandeered it, so I just bought and assembled the truck version for the 3.5 year old. I have to say that they ARE difficult to assemble, BUT with determination and careful reading of the very detailed and clear instructions, it can be done, even by a 71-year-old grandmother with arthritis! It took me most of a weekend to assemble the coupe, but the truck went faster, as I was now experienced!