Here's the system that you should use when you want to charge for your services as a freelance organist which would attract only the customers that you want to work with.
1. Calculate what you are getting payed in an institution.
2. When working privately charge at least twice as much because your costs, responsibility and risks are much higher when working on your own (marketing, technology, education, taxes etc).
3. Depending on how much value you provide, you can charge up to five times the amount you're getting payed in an organization.
4. Never trade time for money because then they can buy your minutes, not hours.
5. Most of the organists I know charge not enough.
6. Then they get a lot of calls from people who shouldn't be their customers.
7. You should choose your customers and never work with someone you don't trust just because they want to pay you money.
8. Always remember, that your customers are paying not for your time but for the result they get from your services.
9. The more vital the result is for them, the more they can pay you.
10. If somebody complains that you charge too much, it simply means, you are not for them.
PS If you don't have enough time in your day, it means you're pricing your services too low or working with the wrong type of customer.