Internet
You can also search for a room per internet. At most websites it is possible to place an advertisement when you are searching for a room or when you want to sublet your room. The costs will be lower than searching with help from an agency. But please be aware that these organizations do not have an office in Groningen and do not act as an intermediary. They only provide users with a database for the search of temporary rooms.
English websites:
Dutch websites: