Where are you planning to open the shop, in the Lakes Region? I would honestly check around first, this area has a very limited Wakeboarding scene, in my opinion. The largest wake-oriented business in the state closed one of it's two shops a few years ago due to limited business.
The remaining shop carries decent equipment, but they are very well established and suck money from the tourists with money on Winnipesaukee. They close during the off season as well, so be prepared to starve in the lean season. You will need a very detailed business model with significant capital to survive.
I wish you luck dude.