Re: How to keep your boat in good shape.
"good shape" needs to be divided--think of all the different ways people keep their cars and trucks "in good shape." There's the show caer in the heated garage driven only on sunny days and washed every thime; there's the family wagon outside that gets regular oil changes and tires rotated.
There are certain things under "maintenance" that are base-line requirements, which will focus on your engine/drive train, lubrication, and trailer bearings.
There are things peculiar to boats such as bottom paint and zincs that depend on your use. salt water/fresh water, shallow water/deep water, moored or trailer stored, all make a big difference on your protocol.
Cosmetic care can be anything, but the base line starts with the way the boat is built--some are made to be left outside and some need to be covered and out of the weather when not in use. And then there's your particular climate--in the mild mid-Atlantic we have a whole lot less to do than those with snow, freezing, or tropical sun. And within the climate, go back to the particular boat and whether it can handle weather or not.
as for washing/waxing, nothing could be a more personal choice--just like a car. Me, personally, I own boats that require minimal care so I can spend more time and less money using them than cleaning and covering them.