WE sold our house in Seattle in 2003 - thought the market was overheated then, but turns out it still had a few more years to rise. We moved aboard, and have been happy since. We have been cruising from Seattle for three years now, and will be leaving for Ecuador in a week or two. Here are a couple of points.
A house is not an investment - it may happen, but 40 percent of America is underwater now - so no need to consider that - but - it is a hard mindset to get away from. We ran rental property for 20 years - its not for the faint of heart
We did not like Seattle anymore and never wanted to go back - rainy, cold, and western WA is very crowded. If you like the area a lot, keep the house and rent it out - if not sell it and don't look back. We have met a lot of folks down here who have rented their homes - they seem to be driven a lot by the need to return home to do work on the house, despite having an agent. It will change the way you plan.
Five months out of twelve the weather will be crappy wherever you are, and it might be nice to have a place to go back to. In MX it is the hurricane season from July to Nov - same for the Caribbean - the Med has its own winter weather you need to avoid - same for the East Coast USA. There is always someplace to stash the boat. You can cruise the Pacific - but that long range cruising is not for some folks.
We are thinking of buying a small house in New Mexico now because of the point above - plus, US real estate is dirt cheap - cheaper than MX right now - its nice to have somewhere to go to when the weather is crappy - it will be someplace we really like though, and not someplace where we had to live because we had jobs there.
There is a lot of value to the vagabond life with no commitments - everything is a trade - but - if you can afford not to rent the house, most of the home ownership issues while cruising are eliminated.