Im not a big DIY guy but when this unit arrived, the stairs and drawers were already assembled. The balance of the assembly was relatively easy (I did end up woth one spare panel, but cant figure out where it was supposed to go because everything looks complete.. Im known to have parts left over) and it looks and functions great. Twin size memory foam mattresses were a tight fit, but acceptable. My daughter and grandson have used it extensively since I built it 6 months ago and it is still beautiful and sturdy. We love it.