We are selling house to a reform couple, where woman is not jewish according to Halacha (she has a jewish father and non jewish mother) and the husband is Jewish. The couple got married through the Reform and I have been informed they don’t have mezuzot in their current home. I am aware that they celebrate the non jewish festivals and have a Chrismas Tree in their home. Are we able to remove the Mezuzot when we sell the home to them and use them for our new home. Our concern is that they will be removed, not treated properly or in a house where non jewish practises are followed.
You may remove the mezuzos. The reason is because we cannot trust that the non-religious person will not eventually rent the house out to a gentile, who won’t treat the mezuzah respectfully. Secondly, in your situation the house itself will be partially owned by the wife (if she signs on the contract) who halachically is a gentile, therefore the one is partially owned by a gentile and therefore according to the Rema the house will not be obligated to have a mezuzah at all.
Igros Moshe Y:D 182, Rema Y:D 286-1.