A good solution to #4 is to get the commitment in writing first. In the sales contract, say they will pay X upfront you will build F by Y date. This solves man

A good solution to #4 is to get the commitment in writing first. In the sales contract, say they will pay X upfront you will build F by Y date. This solves many problems. Customer can’t back out. Gives sales person clear next steps. Clearly defines feature details and deadline. Just make sure you set deadlines you can definitely hit.