mortgage, with the approval of the agency, shall be free of the requirements of said subdivisions (b) and (c). Any contract for sale, lease or other transfer shall be approved by the legislative body before its final approval by the redevelopment agency. Any contract for sale, lease or other transfer to a redeveloper may provide, among other things, (a) that the real property in the redevelopment area shall be maintained in accordance with the redevelopment plan; (b) that the redevelopment agency shall have the right of inspection; (c) that the redeveloper, as security for its fulfillment of the contract, shall make a cash deposit or give a bond with such surety as the contract may provide or make such other guarantee as the redevelopment agency deems necessary in the public interest; and that, if the redevelopment agency finds that the real property in the redevelopment area is not being maintained in accordance with the contract terms and conditions, it shall notify the redeveloper or its successor in title in writing of the work which shall be done to meet the standards of maintenance agreed upon. Unless the redeveloper or its successor in title complies within ninety days with the requirements of the redevelopment agency as stated in such notice, the redevelopment agency may cause such work to be done, and the cost of the work shall be paid by the redevelopment agency out of the deposit herein provided for; and that, if a redevelopment agency, pursuant to this subsection, causes any work to be paid for out of such deposit, the redeveloper shall, within thirty days thereafter, pay an equivalent amount to the redevelopment agency in order to replenish the deposit; and that, if the redeveloper fails to make such payment within thirty days after being notified by the