Rewiring a US boat for the Med is relatively easy, because the wiring
is large enough and you don't have to pull wires, however to wire a European boat for the US will require replacing most of the wiring, which is a huge pain. I will be taking my US boat to Europe
and have been told by a marine engineer
who lives there that I should just bring some US electrical
cord ends with me, and I can purchase
and just cut off the ends of the cord and replace with the US plugs, which I then run off of my inverter. You would not be able to do that in the reverse situation. Same thing with plugging in the boat, I just need a step down transformer, but you would have to rewire that European boat to plug it into an american marina. I have been told that it is not so unusual to find boats there wired for both systems. Maybe you can find that.
One other thing that may be of concern---- in Europe
is not such a big thing, generally deep water
. However, in the US, depending on where you will be sailing, it could be an important issue. You need to keep those things in mind. Also, Europeans are not quite so concerned with all the creature comforts that you tend to find on American boats.