Ah, where to start? I have owned a gym for 35 years now in Sydney, Australia. I have always wanted to have one of the best gyms in the world. I have had an engineering factory since 1981 so design and build most of my gym equipment. The very idea of what a gym is has changed over the years and the equipment has proliferated and improved a lot as well. All gym owners wonder what the formula is to make money. It is no point copying others unless you are buying a franchaise. Golds Gym at Venice is a bodybuilding gym that is profitable so it is possible to have a gym like this. Whether you need to cater to everyone is another thing. The trend is to offer everything and to do that properly you need rooms for cardio, equipment, free weights, aerobics, circuit and child minding. Some have rehab sections. If you have all these services you will need at least 20,000 square feet. I think if you kept cardio machines, equipment and some free weights you could have a super gym in about 10,000 total space. You will need change rooms and offices so you might end up with a floor space of about 7,000 square feet. It might be possible to run the gym with much less staff than you need for the super clubs that have more services. Stick with what you are good at and you might be successful.
We have separate rooms for cardio, pin-loaded equipment, free weights, aerobics, child minding and offices. All up we have about 20,000 square feet and about 80 parking spaces. It is important to have parking adjacent to your club. I like keeping the areas separate for many reasons. Noise, activity and members. The free weights is used mainly by bodybuilders. If you limit the dumbbells to a certain weight you limit who will use your gym. I recommend having several sets of dumbbells and perhaps up to 150 or so pounds for most big guys. You will need special rubber flooring in the free weight area. Get the best dumbbells you can afford. I recommend stainless handles and cast iron plates. You will need lots of mirrors in the free weight area. You would be wise to get at least 6 Olympic sets and possible a few Olympic bars that have other profiles, eg., easy curl bars. Have plenty of plates for everyone and racks for each apparatus. Make sure all benchs have safety rails. That way you cut down on possible injuries. I have designed incline and decline benchs with safety rails. Squat racks have to have safety rails, too. Make sure your benches cannot tip over. Have several drinking fountains available with filtered and cooled water. Have an electronic, accurate scale that weighs up to 550 pounds.
An ideal gym might have several pieces of equipment for each body part. There are so many companies making gym equipment that you could make an exciting gym by having several different machines for each body part. No particular company makes the best pieces for each body part. Try to have as many pieces with weight stacks. There is nothing messier than having plates all over the place. If you want some Hammer equipment then realize not all of their machines are great. Pick a couple and make sure they have weight stacks. They take up less space and don't look so intimidating. You will need ordinary people to help pay for the club. Forget bodybuilders although set your gym up with them in mind. If the bodybuilders don't use equipment then it is probably not that good. You can have sections for legs, arms, chest, back, calves, shoulders, abs, and lower back. Anyone who has trained before will be impressed if they come into a gym that has all the right pieces of gym equipment. You really have to know equipment because opinions vary and be careful about asking others because so many believe they are experts. Make sure the equipment can be used by most people and have big weight stacks to accommodate the strongest users.
It is a good idea to have duplicate pieces of the most used pieces. We have 12 lat pulldown machines. There are many arm stations and many leg extension and leg curl machines. We have 7 leg presses if you count the 2 Nautilus duo squat machines that I modified to make them safer. We have 3 seated calf machines and 2 standing calf machines plus a hack squat calf machine. Some companies are offering apparatus that is multi-purpose and these are popular and easy to use. Again, you could get several of these machines. Install various pieces that women love using. Abductor and adductor machines. Butt blasters and multi-hip devices. If you attract the women you will have men showing up. Install a whole line of machines that suit women and keep those machines to one side of the gym where the women will be comfortable. Trying to get the balance right about dealing with women is a tricky job. I have seen bad set ups work and great set ups fail. You really have to keep changing layouts until you find something that clicks.
My gym has over $1,000,000 worth of gym equipment and some inventions that no other gym has because I made them myself. I have a biceps-supinator machine that I patented that owes me over $100,000 and took me 20 years from conception to completion. I think you could upgrade equipment from time to time and add a new piece of equipment every 3 months. That means you will be adding 4 pieces of equipment every year. For cardio make sure you have the best available equipment and lots of each items. Most gyms have TVs set up so that people can watch while working out. That is expensive to set up but once going should pay for itself.
Get the best instructors you can find and make sure you have sales people on the staff. Do some marketing research and see what people in your area want and what they are willing to pay.
Good luck.
