In each municipality, as herein defined, of the state there is hereby created a public body corporate and politic to be known as the housing authority of the municipality; provided that such authority shall not transact any business or exercise its powers as hereunder until the governing body of the municipality by resolution adopted by majority vote of those present at any regular or special meeting shall have declared that there is need for an authority to function in such municipality. In towns, such resolution must be adopted by majority vote of those present and voting, by use of ballot, if at an annual meeting; and if such resolution is to be acted upon at a special meeting, the procedure for adoption shall be the same as that prescribed for the making of appropriations at special meetings as provided in N.H. Rev. Stat. § 31:5. In any suit, action or proceeding involving the validity or enforcement of or relating to any contract of the authority, the authority shall be conclusively deemed to have become established and authorized to transact business and exercise its powers hereunder upon proof of the creation of an authority and of the adoption of a resolution by the governing body declaring the need for the authority. Such resolution or resolutions shall be deemed sufficient if it declares that there is need for an authority. A copy of such resolution duly certified by the clerk shall be admissible in evidence in any suit, action or proceeding.