Please, help me with some information...

[Vitaly]

Dear Sirs,
I purchased the power boat (length over all is 12.2m; two Cummins 370 engines) from the private person in Italy.
I need to export this boat from Italy to Israel under Italian flag registration.
For this procedure I must have set of documents.
Right now I have following documentation:
- Dichiarazione di vendita di imbarcazione usata (Act of Sale).
- Estratto registro imbarcazioni da diporto (Document of boat registration).
- Licenza di navigazione (Navigation license).
Could you check for me, please following information?
1. If those documents are enough for a legal exportation the boat abroad (leaving Italian territory by sailing with this boat abroad). If it is not enough, please, write me which documents I’m missing (what documentation I must have more for the legal exportation).
2. What is mean “Nulla Osta” document? Must I have this document for legal exportation, or I can export the boat without it? Which document I need for the custom permit / border police?
3. If after exportation this boat to Israel, I will decide to cancel Italian flag registration and register the boat under Israeli flag, is the boat must be in Italia, or, I can do it from Israel? What are the regulations?
Please, help me with this information as soon, as possible, because the winter is very close, and I must to sail with this boat before winter season.