My 17 year old daughter's boyfriend lives in my home rent free. He is 23 years old. Do I need to give him notice if I want him to leave?

Yes, He has established residency. So you have to give him formal, written notice to vacate.

How did you come about letting your daughter date a 23 yr old and let him move in?

I have some serious issues with the parent here, no 16 year old should have a adult 23 year old boyfriend to start with, and for sure not one that is living in the house.

Personally I send the 16 year old child to another family member for a month, and evict the person. ** OK personally it would have never happened, but if it did, I would just do a illegal eviction and let him sue me for rental damages if he wanted to try.

I would control any contact between the two completely.

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Personally I send the 16 year old child to another family member for a month, ....

She's 17, but who's counting?