I would be visiting Italy from May - July 2012. A professor from University di' Sassari has asked me to join him for 2 months. I would be staying a with a student over there.
I need to get a tourist visa for the same. I checked on Italian embassy's website. For proof of accommodation, I either need hotel bookings or Lettere di invito from the host. The letter of invitation states that the host needs to submit a bank guarantee. I wanted to ask if this is really necessary ?