Good luck with the business, I always admire people who have the guts to have a go and stand on their own feet - never stop marketing even when you get busy, it creates next month's income, and it takes around 2 years to build a business to a point where you can have a rest and let it run itself.
Just looking over your website, which looks great, nice and clean, it would help if the main reason for your being was on the home page - avoid getting a $500 on the spot fine, get your PWC licence now. It adds some urgency to the process. Your service shortens the process by helping customers avoid repeat sittings of the exam if they fail under their own steam.
And for later, could you add extra courses like safe boat handling, boat safety in port, prepurchase safety audits etc?
All the best.