Trip to Europe! how much?

hi there: Well 2 of my girlfriends and I are leaving in March, we are going to London first, then going to Paris, then going to Rome. We are staying at budget hotels and doing some tour stuff. Right now with airfare and hotels it is costing about $4000 for 3 people for 2 weeks. i am taking $3000 for food and odds and ends. I hope that is enough. But if you can go..go..I would see about renting an apartment for all who is going. I would not go to craigslist unless u get knowledge up front of any deposits per person per night..That has happened to me. So do lots of research.