before_save :update_price

  def update_price
    self.price_per_minute_2 = self.price_per_minute - self.default_connection_charge if self.price_per_minute
  end

  # Registry.default_connection_fee == 0.2
  def default_connection_charge
    @default_connection_charge ||= self.user.connection_charge.to_s.to_d + Registry.default_connection_fee.to_s.to_d
  end