I started a gym like this about 2 years ago while working 45 hours at my regular job.
I did it soley by myself without financial help or any other staff.
All I can say is you better have the time and money to make it work.
I found out that I didn’t have enough of either. I took about 10 months finding the best priced used power racks, squats racks, mirrors, etc I could and stored them in friends’ garages and at my place. Then I found a warehouse without a/c and rented that. Working out in July - September with only a fan will get your sweating!
I ended up having it for a year. It was mostly a learning experience than anything else for me. My target market was teenage athletes wanting to train sport specific.
There are so many expenses to think about when it comes to starting your own company, especially insurance in this industry.
I still think about doing it again as I gain more and more experience in this industry.
Good luck.