...and although I can't address most of your questions, maybe I can shed some light on the classes and the way they were structured in our shop a couple of years ago.
In our shop, an OW class is $150, and covers two weekends each. That does not include the teaching materials, which is about $60, but does include the rental gear and your C-card processing fee. You need to purchase your personal gear...mask, fins, snorkle, weight belt and weights (usually #10). Of course the shop prefers that you buy from them as this basic gear would run in the market of $250, but it wasn't required and the student was not treated any differently if they didn't buy from us. Some students would come to class with gear borrowed from friends or may have even bought them elsewhere.
Normal class size was 8-10 students, with class minimum being 4 students. Let's use 10 students for this example. Of that $150 per student, ($1500) the Instructor was paid $50 per student (-500) (this may have been raised by now). The store had to rent class time at a local public pool which cost $40 per hour. For the weekend classes, this was 6 hrs per day for Saturday and Sunday, 12 hours total (-$480). No, the students aren't IN the water for 6 hrs. per day but the class was AT the pool. For the next weekends checkout dives at a local quarry, each students entry fee was $30 (-$300) for the weekend. Each students tank had to be filled at least once each day, so 20 fills at $4 (-$80). The dive site does not charge Instrtctors or Divemasters entry fees or for air fills. Divemasters do not get paid for the class. C-Card PIC envelopes $13 (-$130). So out of that $1500 taken in for class fees, subtract $1490 for class expenses. Out of the $10 profit, the shop maintains all rental gear (BC's, regs, tanks) and replaces it at least once a year or more often if needed. This includes tanks. Oh, and the students recieved a T-shirt upon completion of their certification. Cost per T $7 wholesale (-$70). Now we're into the red by $60. This is with a good class. If a student needs more pool time, more of the Instructors time, the shop pays for the pool and the Instructor donates his time....the student is not charged more.
And we haven't even mentioned lease/mortgage payments, utility bills, employee salaries and assocciated taxes, insurance, etc. that is required to provide a place for the academic classroom time and space. The vast majority of a shops rental tanks are for their own use so a big part of the hours used on a compressor is class related. I have no real idea of the cost of compressor maintainence but I know it is vital and something that is done religiously. Since it will be mentioned that these expenses will be covered by merchandise sales, let's just not count them.
That still leaves us losing $60 on a class of 10 students. To be VERY generous, let's say the shop holds these classes every 2 weeks. 26 classes of 10 students, each at a loss of $60 will give the dive shop a loss of $1560 every year on just the classes alone.
Gravy? I don't think so.
