Female-Only Roommate Ads

If one were to advertise for a female roommate in a one-bedroom apartment or rented home that would cost the woman that would answer such an ad $0, what legal rights would the one have to evict the person or how long that individual could stay in said one-bedroom rented facility from another individual? I would guess this would be no different than the rights of a girlfriend living at a boyfriend's apartment; but what are those rights of the boyfriend to evict on whim. I personally would think the person a horrible person to evict a girlfriend on only a whim; but if said girlfriend were found to be a thief or such, the boyfriend would obviously want to get rid of the girlfriend immediately to cease any further threat of theft or other such activity that could harm him. I have personally thought about entertaining such an advertisement as posed above, but also worry about the risks legally (though the personal risks are apparent to me).

IANAL...

All of our circumstances vary, but the idea of taking on someone as a true roommate (ostensibly including some BCD time) in exchange for free/discounted rent seems horrific to me. If I wanted to live with a woman I would marry one.

If I wanted such a barter, I'd be more open to letting a lady stay at a place I owned/paid for with the understanding I "visited" on a regular basis.

All sorts of problems abound with this ignoring the legal ones. Can she date? etc. etc. etc.

From a legal standpoint does she have a lease or is she merely staying as your guest?

If she is your tennant, for any kind of contract there must be consideration. That consideration must be legal. Blowing you twice a week doesn't count. Legal consideration could be as simple as cooking and cleaning or walking your dog. The problem is as long as she maintains her end of the contract she has rights...even if she isn't taking care of your real needs.

On the otherhand, if no formal agreement is reached...she really is screwed...you get tired of her you can toss her...

Even if there was an formal understanding (e.g. she'd blow you), since it isn't legal, practically speaking, she's still screwed. It is kind of the reverse of the guy/client/john paying in advance for a session and not getting what he (thought he) paid for. He has no legal recourse.

Of course if you cohabitate long enough for common law marriage statutes to apply...that is a whole other story but I assume we are talking about months not years here...