When used in this chapter, “municipality” means any town, city or borough, whether consolidated or unconsolidated, and any fire district, and “budget-making authority”, as applied to towns, cities and boroughs, whether consolidated or unconsolidated, having boards of finance or other bodies charged with preparing the budget, means the board of finance or such other body; as applied to towns having no boards of finance, means the board of selectmen; as applied to fire districts, means the district committee.