(a) Before initial endorsement of the mortgage for insurance, the mortgagor, the mortgagee, and the Commissioner shall enter into an agreement in form and content satisfactory to the Commissioner for the purpose of precluding any excess of mortgage proceeds over statutory limitations. Under this agreement, the mortgagor shall disclose its relationship with the builder, including any collateral agreement, and shall agree:

1. (1) To enter into a construction contract, the terms of which shall depend on whether or not there exists an identity of interest between the mortgagor and the builder.
2. (2) To execute a Certificate of Actual Costs, upon completion of all physical improvements on the mortgaged property.
3. (3) To apply in reduction of the outstanding balance of the principal of the mortgage any excess of mortgage proceeds over statutory limitations based on actual cost.