I'm so excited I had to post something. My wife and I are purchasing a house that has a 28' x 28' concrete foundation in the back yard, separate from the house. It looks like it was put there to be the foundation for a future workshop. My wife, being the wonderful woman that she is, is completely fine with turning that into a gym.
Hopefully, in September, when my father comes to visit, we will start putting up walls and complete the structure. After the walls are up, the inside square footage will be 756. I'm soooo stoked. The house is on a 1/4 acre lot so there is plenty of backyard left. I will use a portion of the new structure for crossfit and a portion for my heavy bags and grappling mats. Then all things in the world will be sweet and wonderful.