An existing and proven business model?

I think I'll set up a design business like an insurance company. My customers will have to pay me a monthly retainer to do nothing. If they DO have a project come up, I will raise the rates and make them pay a certain amount of it up front, no matter how many months worth of retainer fees they have already paid. If they have any existing bad design, I will refuse to do any new design work to improve it. And if they ever try to do something on their own that I deem dangerous to good design, I will drop them as a client.

Should work, don't you think?