OK. I am still slightly unclear as to where the Mainship is that you are thinking of buying.
Having said that, the advice above is correct.
So, let me give you my thoughts:
1. if the boat is in Europe and set up for 240v, then no problem.
2. If the boat is in Europe and set up for 120v, then no big problem, that's why the boat is still in Europe.
3. No matter what, I can't see the market for Mainships justifying the cost to ship it to USA. Forget that idea.
4. If the boat is in USA, then see 3 above.
Now, that should have covered all the possibilities.
FYI for people who want to know what they may not know, I have a 120v boat in Europe for two years and have none of the above.
I debated for months and months on the advice above; all correct I may add, but I have gotten around it.
I have kept the boat isolated from each electricity. I have one 220v charger that is plugged into shore power (240v).. It is not using the boat ground, but the 240V, I actually unplug it and have a different plug when using boat, Gen power.
I have a few 240 appliances and lights that are alos plugged directly into 240 power and are not connected to boat system at all.
While looking a bit clunky with extension cords and power strips, it works very well.
lastly, in Ireland, EU made and certified 240 to 120v transformers are readily available for $75, since in Ireland outdoor tools are only supposed to use 120 power. Thus a big market for transformers. I have that plugged into Raritan water heater. Though I have also obtained a 240v heating element for the Raritan, thinking that once I replace the heating element, it will still work with 120v , but just take twice as long to heat water. Since i almost never use the Gen to heat water, not a big deal.
Email me if you want more specific advice.
Richard