Do not continue to exchange hours for dollars. It is a losing game. You can never win doing this. Bill only by the project. And get paid according to percentage of completion. In addition, charge a royalty whenever possible.

Charge $A up front. $B per month, and $C per %completion, $D as an ongoing royalty, and $E for future contribution which varies according to your contribution.

I hope this helps.
Best of Luck,
Mike

PS I may assist you as my time permits. Right now I am doing something that I haven't done for many years. I am actively soliciting new select clients due to selling one of my businesses and freeing myself up a little. But as you might expect, I am still very busy. That is how I like it.
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