Thanks anyone for your replies! All of them so usefull.
In terms of how to make a business plan and all the variables to consider when running the business (competition, location, price movements) I can say Im quite solid. What I need is infos about machinery, everything you might know about fish, how to keep it, where to find the best even if Brindisi is on the sea, whether websites like
Sushi Fornitori are good sites where to buy ingredients etc. Thanks again everyone. A