Terrible plan. Biggest part of which is that I forget what percentage of the population lives along the coastline, but it's MOST of it. So you'd be heading into MASSIVE zombie herds to find this boat. And you want a big yacht? Now we're talking bigger populations to find communities that can afford them. And they're huge gas-guzzlers. Fine if you just want a nice boat to drift off and die at sea in, but not much else. Every time you pull over for gas (and it would be OFTEN), you're heading into heavily-populated areas to find marinas to refuel at.
Correct answer (if you already lived close to water, not worth it if you're too far away) was SAILBOAT. They run on magic instead of diesel. One with a windmill/turbine on it (and many do have them) would even keep your batteries charged, so you'd get lights, electronics, fridge/cooking, maybe even desalinization if you stole a nice one. Harder to pilot, but a much nicer option.
Either way, key to surviving these sorts of things is to be as far from a population center as you can. preferably when it hits, but definitely head there after. Heading back into populated areas would be suicide. Long after initial outbreaks, it may be worth going back, if only to loot from the dead cities, but not while it's still this active.
Good points. I guess I was thinking of some of the more rural coastal areas here in GA and near the GA border like Tybee Island, Hilton Head SC etc which are beach communities but not large population centers because they are vacation destinations.
In Hilton Head for example, last time I went there are some really, really big yachts that are moured there year around even though owners don't live in Hilton Head.
BTW, Hilton Head would be approx 4 hours away for Rick and group from where they are here in GA for the show.