I disagree with others here saying what you’re proposing is unethical. It depends a lot on context and what kind of agreements you’ve already signed. If the cli

I disagree with others here saying what you’re proposing is unethical. It depends a lot on context and what kind of agreements you’ve already signed. If the client sees it as a core part of their business or you’ve signed something that limits your options, then it’s on the less ethical side. However from your description it sounds like the client see this as incidental to their business and just a tool they want. In that case I see no reason why you can’t have a conversation about other options with them. I think it would be very reasonable to offer them a much lower rate plus some kind of long term SaaS contract options in exchange for the IP and rights to sell the service to others. They may say no but you could discuss it at least.