The girls have been asking for a swing set for a long time. We've been looking on Kijiji for a few months and finally found something we thought would work. Unfortunately it wasn't quite up to par interms of strength, but the slide, swings and the majority of the lumber was used.
A number of years ago Ben built a sandbox with a lid that turns into benches. We wanted to incorporate that into the swingset as well, so we had to go custom. We moved it to the opposite side of the yard where the swingset would go and Ben built the playhouse portion around/above it. We kept the lid (I'm paranoid about neighbour cats) and it still opens and gives enough room for playing.
The swingset portion we basically kept intact and Ben reinforced all the beams and supports. We have two VERY happy girls who have spent hours each day swinging and swinging. Katie learned to pump last year and Emma figured it out within two days of the swings being hung. That was a good day in my books!