On the water and off. A septic system near the water is often the biggest hurdle for housing, even existing if they want to expand or as older systems give out. Now you can approach zoning planning boards needing only grey water treatment in some instances, if you're willing to live with a composting toilet near the shore.

On boats like a shanty boat, it makes you legal in many waters where any overboard discharge is prohibited. That includes most lakes. In Lake Champlain for instance, they could fine you heavily for having any means to pump overboard, any(ties, wires on overboard seacocks, none of that was legal).