Recently I helped a fellow yachty install one of those onboard combo units in his 48'' ketch. They are much heavier than you might expect when you see the package, so be carefull about displacement of your weight.
I live aboard my 38'' steel ketch (now in Australia) about 1/2 of the year and find most marina''s to be really well stocked with washer/dryers. You''ll find that your cloths will become more and more casual as you settle into the life aboard and thus your laundry days will lighten up. Like the rest of us, you''ll be hanging your "fine washables" along the life lines. Regards,