Easy to assemble and my 6 mos kitten and 18 pound Norwegian Forest cat battled for 3rd tier with the hanging mouse on elastic string (think the toy is catnipped! perfect touch) The Condo was the first place to explore along with the jute wrapped columns tested on every level. Huge success, my three cats took to it instantly with the sense of curiosity and adventure. An ideal size for multiple sized cats fits in a corner as the base isn't set square but on the diagonal. Would definitely recommend to others.