My preference would be to start out with limited, but versatile equipment. I started my business with jump ropes, adjustable steps, dumbbells, adjustable dumbbells, pull-up bar, bands of all different resistance amounts, a suspension trainer, cones for different types of drills, an exercise ball, a ten pound medicine ball, a small bench, etc. Total start-up costs of under $1,000.
If funding pressures are less for you…you have more options and more decisions to make. Best of luck to you with your new venture!