If a trustee is entitled to "reasonable compensation" under the trust instrument, the key question -- as you have already concluded -- is whether the value of the rent-free occupancy of a furnished home exceeds the compensation to which the trustee is entitled. If the trustee is not complying with the terms of the trust, is not exercising due care in the administration of trust assets, or is not being impartial to all beneficiaries, the court can reduce or eliminate the compensation to which the trustee would otherwise be entitled to. A trustee can be required to pay the trust for benefits not covered by the amount of court-approved compensation. It is impossible to predict the chances of success in court, but from the facts you have given, it would appear that your position is sound and that a petition under NRS Chapter 153 is justified.
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"Can I expect success by petitioning the probate court if she refuses?"
Whenever you are dealing with the court, you cannot reasonably expect anything, but based on the facts you've recited, it would not be foolish to ask the court for the relief you've described.