As the others have said, looks like a typical near 20-year-old boat cruiser stern boat with poor deck board drainage - as far too many have. Why the deck boards are not draining, if that is indeed the case, needs investigation because it might just be fully or partially blocked overboard drains or it might be poor design. In many cases poor design can be improved. I don't think the exhaust is leaking because I can't see any soot around that area, and it looks as if the exhaust flexible might be convoluted stainless pipe, rather than spiral made galvanised flexible. If so I suspect that the length of the flexible is marginally shorter than ideal, hence the bend close to the manifold. By the look of it the "lock" wire rings that normally secure the end of the heat-resistant bandage to the flexible section are loose, so what Mike calls duct tape may be metal foil hiding the frayed end of the bandage. If it were ordinary duct tape I would expect it to be badly burned or discoloured. In my view it would take a good number of days to clean the whole bay, treat the rust and repaint, but that would be the case for the majority of similar private boats. In any case that is something that would need doing regularly, but would take less time once the initial job is completed. It is perfectly possible for a reasonably practical boater to do it themselves, but not until next summer when the temperature is warmer.
