In Sundsvall county, there is a housing guarantee for full-time students at Mid Sweden University. This is done primarily through Mitthem but also through other actors. There are many different types of housing ranging from shared corridors to 2 bedroom apartments. However, what is out there varies when you apply. Therefore, make sure to be out in good time.
For more information and to register for a home is done on their website https://www.mitthem.se/artikel/student
Other actors that exist are:
Härnösand (50 km from Sundsvall)
Timrå (20 km from Sundsvall)