Leasing Space to install own boxing boutique studio

Yes. I’m going on about 13 years now in the industry and have been independent now for 2 years going on 3. I currently pay rent at a gym as a trainer to run my business out of. Come July we will be moving from a 3,000 sq ft facility to 10,000. And looking to lease space to build out a boxing boutique studio inside. Needing around 1,500 sq ft for this.differnece here is no longer paying rent month to month using facility. I will have invested in an actual build out of the business model inside with use of the rest of the facility to also continue with my private training and small group as I currently do. And now have a group boxing studio inside to continue to build an membership base for classes. Would I treat this the same way as I currently do? Or how would I determine rent having invested in a section with flooring, equipment etc that my business needs. As I feel this is still the cheaper route then leasing a separate building ? Thoughts?