Good Idea TR, a lot of the local schools in VA let the players use the Gym for workouts on the weekends.
We are fortunate enough to have a small building we rent from the local 4-H and it's big enough to fit two cages in and a row of tees and a mound. We heat it with a kerosene construction heater and it serves the purpose. We even have a dirt floor so they can wear cleats. We pull up the cages and take infield as well.
CV