I did this in my current gym with great results, after a 3 month study I went from having 0 sessions a week to 8-15 sessions a week and this happened straight away.
The client I used was very motivated and willing to stick to the nutrition plan and training, it is so important to pick the right person as you could waste a lot of time and effort if they don't stick to everything which will then affect your results!
After 12 weeks the before and after results are as followed..........
Weight: 66.2kg 59.5kg
Bodyfat % (Machine): 34.2% 25.6%
Bodyfat %: 29.6% 21%
Waist: 30 26
Hips: 40 38.5
Arm: 11 10
Thigh: 22 19.5
Overall the results were great and she looks fantastic..... This could really boost your client base to a whole new level!!!