This Would Be So Much Easier Without Client Categories

So I have this person who is considering whether or not to retain me. I really think that this person's case is marginal at best. I keep telling this prospective client this, but the prospective keeps coming back with more and more questions.

To date, I have not signed this person up as a client, but I am starting to get the feeling that if this person does not make up their mind soon, I am going to start to charging just because of the amount of time I am wasting while they go through an endless-decision loop.

It makes me want to grab the prospective client and yell at him "Make up your mind!"