22 year old boy History student from Milano

I'm going to Lisbon for Erasmus at Iscte. I'm coming in the same period as a friend of mine from Milano too who's going to study at a Nova campus 30 km away from Lisbon: therefore we'd need a place that's near both to the yellow metro station (Rato, Marques de Pombal) and the green one, so that I can easily reach Iscte and he can easily reach the railway station (Avenida metro stop would be great). We'd like to live in an international apartment with 4-5 other students, in separate rooms.