Re: what type of gas generator would i need for
OK. The first thing you might consider is replacing the water heater with a heat exchanger style. They've got an additional pair of fittings for engine coolant to circulate thru and keep the water hot without using any electricity. I have a 10 gallon unit and the water will stay hot all afternoon after shutting down the engine.
Now, the genny- if you don't run everything at the same time, you could get by with a portable like the Honda eu2000i. It's NOT designed for marine use and must always be setup so carbon monoxide can't collect in the boat. They're about $900, which is less than half of a small installed marine generator.
OTOH, if you spring for an installed marine genny, your AC power is just a pushbutton away. I think a 3kW model would do the job, but a bigger one would allow an A/C unit to be added in the future. Either way, your boat's value will go up considerably with a proper marine genny installed.
I'm currently in the process of installing a new 5kW Kohler "low-E" model in my boat. It's a big job that requires a lot of planning (and money!) but so far so good.
