code: def apr
        @apr ||= MortgageBuddy::AprCalculator.new(loan_amount:               @loan_amount,
                                                  monthly_payment_with_fees: monthly_payment_with_fees,
                                                  period:                    period,
                                                  monthly_interest_rate:     monthly_interest_rate).apr
      end
docs: == Parameters
   [:loan_amount]  Loan amount. Price of home minus down payment
   [:interest_rate] The interest rate of the loan
   [:period] Number of months of the loan. 30 yr is 360. 15 yr is 189
   [:fees] Closing cost fees. Optional and defaults to 0
   [:points] Points. Optional and defaults to 0