this has all been done before, but
a well known inland site would pay you £100 for teaching an OW course.
Then think that is a minimum of two full weekends or pool and shallow water work. = £25 for at least an 8hr day
then add on medical, insurance, kit etc...
go on your own and you could make £50 to £100 profit per student. 2 courses a month, 12 students = £1200/month profit. Knock off all your personal fees etc... you make more being a dustman
not worth the time and effort
a