Well, it's not as if he asked you to help him spring off a windward dock on his way to Costa Rico, thankfully . He was "dream" talking. A firm suggestion that he have the boat safety inspected free by the CG and take a basic boating course, say at the local Power Squadron is all, I think, would do. I would be leery that he bought a boat in the first place, that he may be unsteady mentally. It's to your credit that you think about this.