I cant tell you about putting it together, because my kids (14  15 yo) had it together when I got home from work. So i imagine it was easy to put together. We have 3 kittens, 6 months old and a 10 yo. The kittens love it. They wont use it alone. But theyll use it with the laser light or the feather thing that came with the wheel. My old cat has no interest in it other than sleeping in it. It has the lock, but we havent needed it. It doesnt move that easy. But it is easy enough for the babies to use. We love it. We have so much fun playing with them on it.