My cats live this thing and so do I! So awesome to have all carpet rather than the fleecy stuff most are made of. I put it together easily, I can move it back and forth in front of the window, I can see from when my cats jump up and down on it (my heaviest is literally 20 lbs) that it doesn't juggle all that much. So the base is large enough to hold this thing and the trays are so so deep! Very well made, Thank you for a terrific cat tree!