I would think that they might not do it unless they trust you and have a big monthly allowance on broadband.
The thing with this is security of the system. Why dont you look at the mobil broadband supliers. They are not to expencive now. My son swears by his. He packed in his home telephone and got it shortly after and thats all he uses. The plus with that is, if you have a laptop you can use it anywhere.