This kit produced two very good pup trailers. The most difficult part of the assembly was the roll-up rear doors. This procedure takes a great deal of patience, caution, attention to detail and persistence. Removing the door panels from the sprues is the first step in care and patience. Don't cut more than indicated or the doors will not fit in the track. When sanding, sand a little and check to see that the panel fits in the track and goes all the way up. The bottom panel of the roll-up doors is not designed to move through the curved part of the track. Take your time and you will get a good result. This kit should be labeled Skill Level 4 or 5.