(a) Where the estimated cost of construction or substantial rehabilitation is more than $500,000, the mortgagor shall furnish assurance of completion in the form of corporate surety bonds for payment and performance, each in the minimum amount of 100 percent of the construction contract (or Guaranteed Maximum Price, in the case of construction management) and each satisfactory to HUD.

(b) All types of assurance of completion shall be on forms approved by HUD. All surety companies executing a bond and all parties executing a personal indemnity agreement must be satisfactory to HUD.

(c) A mortgagee may prescribe more stringent requirements for assurance of completion than the minimum requirements provided for in this section.