You need to work out a realistic business plan

With what you are suggesting, advertising is going to be a large, reoccurring expense
Cost of materials for attendees
Cost of rental for the building you will need
Insurance is a must, but it is not as expensive as some people may be leading you to think
And a weekly income for yourself

As part of a government department, you got paid if you trained one person or a hundred. With your own business you need a constant traffic. How will you go during winter months when your services are not needed as much?

Also, before there were others who could take bookings, answer enquires.
When it is your business, it will be just up to you. You will need to be contactable from earlier than 9.00am until at least 6.00 pm, seven days a week


I think it will be hard for anyone to make this work

I tend to agree hence why you almost need to have a fishing tour business and ski training etc all rolled into one business to absorb the quiet times.

Though you could have a heap of pinnies (@ $1 a game) in the room next to the training room next to your boat shed and boat hire and a Fish Tales Cafe