I have just moved to Italy and bought a car. I am a resident here though(just!) but I know from my experience that they wanted to see my residency and code fiscale (like national insurance number) etc before I could take it and wouldn't let me drive off without being insured (for which I needed these documents again). I think you might have problems, Italy seems to be paperwork crazy! For prices of vehicles, take a look at Italy's e.bay and check them out there (on ebay's home page, other countries are listed at the bottom).