It was very easy to put together and it's not that bad size wise. I will say however that the bottom level is much shorter height wise and the entrance is smaller to that section of the tower. I really feel like they could have made this a little taller overall so that all three levels were more spacious height wise. Also having optional slats for inside would have been nice so you can customize the interior layout (like if you have food bowls, beds, etc. inside it makes it hard to have the right space for them. Overall its nice, but it definitely wasn't my first choice, but all of my other choices were sold out.