I would budget for spending at least $100 dollars a day while in Italy. With food, hostel room cost, transportation, and touring/entertainment (this is the most expensive), it can get pricey! I would consider how long you will be staying in Italy, what the cost of your hostel is, and just how much traveling/touring within Italy you want to do. Then work out a daily budget for yourself (including Asia) before you leave, and stick to it!