My neighbor, who is a bit of an entrepreneur, had dirty fuel problems
in a cruising sailboat. When he tried to find a service to polish his
fuel, there wasn't one.
So his idea is to start such a service. Finding a serviceable old
bowpicker or such with deck space for barrels, hoses, spill gear, etc
and traveling marina to marina with pre publicity to service all those
pleasure boats that feel they may have a need.
So, is this feasible? Enough customers for a reasonable income? What
would customers be willing to pay? Bill by minimum charge and then by
the gallon or poundage on top of that?

If you feel this is spam don't bother answering. Just plonk me! It's
not spam, it's just looking for help to maybe set up a service you may
someday want.
Thanks
Gordon