When real estate is subject to a contingent remainder, executory devise, or power of appointment, the superior court may, upon the petition of any person who has an estate in possession in the real estate, and after notice and other proceedings as required by this chapter, appoint one or more trustees and authorize him or her or them to sell and convey the estate or any part thereof in fee simple, if the sale and conveyance appears to the court to be necessary or expedient, for such an amount, and on such terms, as the court may deem proper; and the conveyance shall be valid and binding upon all parties. The trustee or trustees may, in the discretion of the court, and upon such terms and conditions as the court may prescribe, execute a mortgage of the estate or any part thereof, which mortgage may contain such powers of sale, conditions, and covenants as are usual in mortgages taken by savings banks in this state. Notes secured by, and covenants contained in, mortgages executed by the trustee or trustees, so far as those notes and covenants are made by the trustee or trustees in his or her or their representative capacity, shall not bind the trustee or trustees personally, but only the trust estate.