I think as long as you stay in Italian waters, you will find they will accept what ever
documentation you have. I have been told that all they want is to know is when you entered the country. If you have been to a non EU country and return to
Italy, when you arrive in
Italy check in and show some reciepts from the non-EU country and they don't go any further than that. Italy is in may ways less centralized than the US. There is a lot of reginal independence. To me, I think every unit of
Government likes to rather arrogantly thumb their noses at the central
government and it likes doing that to the EU(politely of course). I sort of gather the local govenment does not get anything out of collecting the tax. Now when you sell the
boat, the next guy will probably get caught for the VAT so it looks like you might get your
money back then.
But Tunisa is a delightful place to spend a year or so - so I would be temped to play it safe and stay there 18 months.
Sure is a bit scary isn't it. I also gather there are no fines. Sort of pay it now or later or maybe not at all. My Marina Operator really went all out talking to customes etc a couple of years ago for me. So far no questions- but it was desirable for me to be out of the EU for well over 18 months.
Good luck. Cheers. Page