My mother used to work in a real estate office, and many years ago they were really happy when the social welfare office showed interest in an apartment: the social welfare office paid, and after moving out, the original condition was restored without any debates. (i.e., any damages that may have occurred were repaired) As we say in Bavaria: that was a piece of cake.
At some point, the idea came up that it is discriminatory for a social welfare recipient not to be allowed to handle such matters themselves. Therefore, they now receive the money for rent from the office directly, and the rental contract is made directly with the tenant and no longer with the office.
Now you might be lucky and the social welfare recipient uses the money intended for rent exactly for that. Then everything is fine.
Or you might be unlucky and then unfortunately have the short end of the stick.
And from painful experience, I can say: it takes time to get a tenant out of an apartment, even if they don’t pay rent. But you are stuck with the costs caused by any damages and/or court costs (you have to obtain a judgment to get someone out of the apartment, which takes time and costs), eviction costs, rent arrears, etc. Of course you can sue! Only: if there is nothing, no one can get anything, even the most beautiful judgments are no help.
Therefore: I wouldn’t do it anymore.
As a landlord, you always have a certain risk which can be minimized if you find, for example, a guarantor (the option parents guarantee for a student is good!), someone who already has a long-standing employment relationship with a good employer (the probability of losing the job is rather low), someone from your circle of acquaintances whom you trust, etc.
In any case, obtain information about the employment relationship!
One-room apartments unfortunately have the property that they are usually only occupied for a certain period of time (then family formation happens or one earns better and wants to live more comfortably, etc.). Which is not only a disadvantage for the landlord, because it is not at all easy to get a long-term tenant out of the apartment.
In a student city, I would definitely prefer the option of a student with parental guaranty (please request proof of income there) in any case. We had the best experiences with that.