If you're going into business I'd also recommend getting a more aggressive one-step cleaner/wax like the Marine 31 Heavy-Cut Cleaner Wax.
Marine 31 Gel Coat Heavy-Cut Cleaner Wax 16 oz.
Marine 31 Gel Coat Heavy-Cut Cleaner Wax 32 oz.
Marine 31 Gel Coat Heavy-Cut Cleaner Wax 64 oz.
This product uses a very high-tech abrasive technology so it won't scratch and scour gel-coat or painted boats like most marine cleaner/waxes.
You always want to be safe when working on other people's boats.
Also, you want to try to stick with one-step products when you can because they safe steps and thus save time.