FinancedPurchaseSavings constructor
      
      FinancedPurchaseSavings({ 
    
    
- Money? annualLoanPayment,
 - double? loanInterestRate,
 - Money? rebateValue,
 - SavingsOverTime? savings,
 
Implementation
FinancedPurchaseSavings({
  this.annualLoanPayment,
  this.loanInterestRate,
  this.rebateValue,
  this.savings,
});