Dead man docking : a bed-and-breakfast mystery / Mary Daheim.

Enhanced descriptions from Syndetics:

Nobody does it like Daheim -- the USA Today bestselling "Reigning Queen of the Cozies" (Portland Oregonian) whose delightfully zany Bed-and-Breakfast mysteries set the genre's gold standard. Now get ready to cruise along with the incomparable Judith and Renie as a well-earned vacation is beached by mystery, mayhem, and hilarious homicide.

Dead Man Docking

Who in her right mind would turn down a free cruise to the idyllic isles of the South Pacific aboard an ultra-luxurious luxury liner? Certainly not Judith McMonigle Flynn -- which is why she and her closer-than-a-sibling cousin Renie Jones are leaving behind the stress of Hillside Manor B&B and hightailing it down to the San Francisco Bay to board the magnificent San Rafael, the pride of the Cruz Cruises fleet. The cousins sail into the pre-launch party on a wave of happy enthusiasm ... which, unfortunately, is about as far out to sea as they will get.

The problem is the piano -- or rather, the corpse stuffed in the piano: the body of their awol host, Cruz Cruises CEO Magglio Cruz. So the boat trip is postponed, leaving Judith and Renie footloose in Frisco -- except for the fact that they're both murder suspects -- and free to gad about with the other marooned, disappointed landlubbers, including one who is a homicidal loose cannon.

Among the almost-shipmates, the cousins are inevitably drawn to Rick and Rhoda St. George -- a picture-perfect team of glamorous, martini-quaffing, would-be crime-solvers. And since no one has anything better to do, they all decide to work together to solve the crime.

When other stranded San Rafael-ites inexplicably begin turning up dead all over the City by the Bay, Judith, Renie, and the St. Georges realize that if they're not careful, they, too, may end up leaving not only their hearts in San Francisco but the rest of their mortal remains as well!