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As tenants in common or even joint tenants, you are not required to pay him rent as long as you give him the opportunity to reside in the house as well. If your brother does not want to reside in the house, then you do not have to pay him rent. However, you if you're residing in the house and not allowing him the opportunity to reside in the house as well, you will owe him the 50 percent of the fair market rental value of the home.
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