We wanted to make a playhouse for the kids, but their two cribs were taking up too much room in their bedroom. So we made a bunk bed playhouse using the crib mattresses.
Here is a tour:
Instead of a ladder, we put a climbing wall in the middle. We found these awesome climbing wall grips/handholds on amazon:
They are super strong, high quality, and were really easy to attach. 
I had found some plywood on a side street anyways and needed to use it for something, so now it is a climbing wall.
I had found some plywood on a side street anyways and needed to use it for something, so now it is a climbing wall. 
We have not done much in the interior yet, but we moved the kids play kitchen inside and a table a chairs. Christmas lights are on clearance right now so we used a couple strings to light the interior.
