Liveaboard in DC
I'm now in San Diego---81F here yesterday, low of 50F, sailing twice a week in my liveaboard Jeanneau 36i. BUT . . . I lived aboard the same boat in DC last winter and it was challenging to say the least. Since I knew I was headed for SD, I opted not to buy heat/air. I didn't want to leave any 110V device on while away at work, so sometimes it was 40F below at the end of the day. I didn't have much luck with the oil filled heater, so I used a 110V Black and Decker garage heater. 40F at 5pm, but the little heater had it up to 60F by bedtime. That, a 110V electric matress warmer, and sweats kept me alive and fairly happy on my new boat.
No worries now . . . SD is the best . . . year round sailing, year round golf, and the natives are very friendly!