Anybody have thoughts on how much time to invest in a closing a client?

Anybody have thoughts on how much time to invest in a closing a client?

I’ve been finding that with some of my prospective clients there seems to be a near endless back and forth before anything solid can be established and work can begin.

A lot of these projects are blockchain related and the clients have varying experience/understanding and will have a LOT of questions before agreeing to begin.

And at times I feel the discussion gets into the realm of me providing SME advice that I don’t think should really be free.

On the other hand, the clients can potentially lead to significant revenue if I stick it out.

Thoughts?