When you say "selling", do you mean she is selling the property or renting it out because your lease is terminating? Unless your lease provides that she has to give you notice or otherwise, typically a landlord, as owner of the property, has the right to access the property at his leisure. Ultimately, it is his property. However, you can request that notice be given and you be present in the interest of protecting your personal property, but absent a provision in your lease that lays this procedure out, your landlord is not required to give you notice of visits or showings.
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