//1. constructor:
function CarMaker() {}

//2. Factory Items Iteration:
CarMaker.Compact = function(){};
CarMaker.Convertible = function(){};
CarMaker.SUV = function() {};

//3. public methods:
CarMaker.prototype.tool = function() {};
CarMaker.prototype.drive = function() {};

//4. Static methods:
CarMaker.factory = function(type) {
  var constr = type;

  if(typeof CarMaker[constr] !== 'function') {
     throw {
       name: "Error",
       message: constr + 'not exist'
     };
  }
  //inheritance only once
  if(typeof CarMaker[constr].prototype.tool !== 'function') {
    CarMaker[constr].prototype = new CarMaker();
  }

  return new CarMaker[constr]();
}

//5. Usage:
var camry = CarMaker.factory('Convertible');
var cherokee = CarMaker.factory('SUV');
camry.tool();
cherokee.drive();