It would be helpful to know what your facility’s space and design are, and whether you just want to rent an exercise room, for example, or also use of your equipment, of if you have unused meeting rooms, and whether you wish to rent during your own down times, or if you just have extra space that can be rented on a semi permanent basis.
Also remember to check with your insurance to make sure if you sublease to someone, particularly someone whose services are different than your own, there will not be an increase in insurance that will eat up any profits.
Depending on your layout and soundproofing if you have a private room you might be able to rent to a bodywork practitioner. Many who do massage or Reiki or things like that are independent, and even if they have a regular space it can be good advertising to take some clients at another space. And the good thing is if you do not offer that yourself there is no competition. You would need to determine going rate in your locality to determine space rental, and check with your insurance company.
We are currently 4000 sqaure feet about to add another 2000. So, one big room we have for our cardio classes (Kick Boxing, Step, Zumba, etc.) as well as our barre clases complete with spring floor. The next room we have set up for our group training classes, and the new 2000 sqaure feet will house our spinning and boot camps. Since we are class based we have down time from about 1030am until 430pm most days. We can bring in trainers, but looking for some out-of-the box ideas. We really don’t have sound proof room for massage. Tried getting in a nutritionist since we have office space for that, but really looking to add more. I know there are Zumba Master classes, maybe some studios host these events and charge a fee for use of facility. Not sure just trying to really make use of the space the best we can. Thanks for any help or ideas that may be working for you. 🙂