1.  Limitations on amount of outstanding principal.  The Maine State Housing Authority may not at any time have an aggregate principal amount outstanding, in excess of $3,000,000,000 of mortgage purchase bonds secured by the Housing Reserve Fund or a Capital Reserve Fund to which section 4906, subsection 3, paragraph A applies. Mortgage purchase bonds of the Maine State Housing Authority secured by capital reserve funds to which section 4906, subsection 3, paragraph A does not apply, bond or mortgage insurance, direct or indirect contract with the United States, purchase or repurchase agreement of guaranty with a banking or other financial organization or other credit arrangements securing the bonds may be issued up to $100,000,000 per calendar year in an aggregate principal amount outstanding at any time not to exceed $300,000,000.  

2.  Bond rating.  Mortgage purchase bonds must be rated at or before issuance of the bonds in a rating category of A or its equivalent or better by a nationally recognized rating agency. A rating is not necessary for any issue of mortgage purchase bonds which: