As long as your father is not on the deed you could evict him once you have title, but you may have a problem with adverse possession. If he has lived in the property for more than seven years and paid the taxes and insurance, he could have a claim.
You should consult with a real estate lawyer before making the purchase.
This communication is not intended to create an attorney/client relationship. It is always recommended you consult an attorney in person to discuss your case. The Law Offices of Stage & Associates practices state-wide and represents homeowners and community associations. Please visit our website at www.stagelaw.com.
The first thing, as Attorney Stage points out, is to make sure that your father is not on the title, can't make an adverse possession claim, and isn't entitled in any other way to half of the property due to his marriage to the owner-of-record (your mother).
Once you have established that he isn't part owner and isn't entitled to claim such, then you can file an action for removal.
If there never was an agreement for him to pay rent, then he never was a tenant and it would not be an eviction action.
The other two choices are ejectment and unlawful detainer. If your father can't raise any objections about being the owner, then the action to file is unlawful detainer, which is similar to eviction (but it for removal of non-tenants). If your father could raise a defense that argues he is or should be part owner of the property, then the action to file is ejectment.
I recommend that you make an appointment with a real estate attorney in your area to discuss all the possibilities. Good luck!
I agree with the excellent answers given by my colleagues.
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