23 years old girl with sister and their puppy, looking for accommodation in Thuringia

We are two sisters and a puppy who will come to Germany for studying in University of Erfurt Intercultural studies.We are travelers, animal lovers and volunteers. We both have been in Germany, Arev as an au-pair and me as a volunteer with kids. We love helping and making new friends from different cultures. We are easy-going persons . We both speak English and Russian fluently. Arev knows a little German and we both are improving our German skills.  We are looking for an affordable room, apartment, dorm shared by students in Erfurt or in all Thuringia.