Are you asking if you need an EIN for yourself or for the gym (to whom I assume you may be sending the 1099-MISC to report the rent)?
Generally, YOU need an EIN only IF you have employees in your business (which you probably don't).
To determine if you need an EIN for yourself, please see https://www.irs.gov/businesses/small-businesses-self-employed/do-you-need-an-ein
But if you are referring to filing a 1099-MISC to report the rent that you pay the gym, then not having the gym's EIN will make it impossible to file the 1099-MISC electronically. You would still be able to file the paper copy, though.
Note that generally payments to a corporation (including a limited liability company (LLC) that is treated as a C or S corporation) are not required to be reported on a 1099-MISC. So if the gym is a C or S corporation, you do not have to file a 1099-MISC for them.
Are you asking if you need an EIN for yourself or for the gym (to whom I assume you may be sending the 1099-MISC to report the rent)?
Generally, YOU need an EIN only IF you have employees in your business (which you probably don't).
To determine if you need an EIN for yourself, please see https://www.irs.gov/businesses/small-businesses-self-employed/do-you-need-an-ein
But if you are referring to filing a 1099-MISC to report the rent that you pay the gym, then not having the gym's EIN will make it impossible to file the 1099-MISC electronically. You would still be able to file the paper copy, though.
Note that generally payments to a corporation (including a limited liability company (LLC) that is treated as a C or S corporation) are not required to be reported on a 1099-MISC. So if the gym is a C or S corporation, you do not have to file a 1099-MISC for them.