4 french students searching for a 4-5 room flat renting

We are four french students searching for an apartment to live in Berlin this year. We are a joyful group of Young people, loving meeting new people, partying and enjoying our student life in the incredible city that is Berlin. We would like to visit the city a lot, as there is so much to see. We are all here because of an internship we are doing in the fraunhofer Institute, in Charlottenburg. So we're gonna work for a large part of the year in the institute, located at the north-west of Charlottenburg, that's why we would like to live in an apartment possibly located in moabit, Charlottenburg, wedding or maybe kreuzberg. We are good friends for 2 years and we know each other's really well,