All what you need to know about registration at the municipality!
Are you looking for a room, studio or apartment etc. in The Netherlands for longer than 4 months, the Dutch law says that you have to register at the municipality in that case. You need a signed rent contract for registration. Or at least an allowance from your landlord that you stay in his apartment.
In many cases your employer, internship or your study finance require registration too, sometimes even when the term is less than 4 monthts. So important for you to verify!
In Amsterdam there is a special rule, which leads to the sitiuation that only 2 residents can register. Not more, unless the landlord has a special permit. But most landlords haven't such a permit.
Some landlords say that they have costs when you register at the municipality. That isn't true. But I guess that they mean that they receive a lower housing allowance or lower social security. That isn't a good reason. And makes clear that there is a big chance that the rent out is illegal!
The best advice is; if you live stay longer than 4 months in The Netherlands, always register at the municipality.