Shared Room
によるポスト Frank (confidential) に ドイツ フォーラム
If you meant room in a shared flat: Yes, that is common (and called "Wohngemeinschaft" or WG). The price is, as I mentioned above, from EUR300/month if you rent unfurnished and for longer periods.
If you meant several people sharing a room: That is incompatible with the German sense of privacy and therefore unheard of.