This cat tree was very easy to assemble and came with all the parts/tools.  It is suggested that it be placed in a corner or anchored and that is a must.  My 1 year old cat loves it!  He plays on it, climbs it, scratches it, leaps from it, and sometimes naps in the cubby hole.  If he's happy, I'm happy!
The only thing that isn't wonderful is that it's a bit wobbly.  maybe a larger base would be helpful.