public ActionResult AddCalculationEntry(MortgageEntryViewModel entry)
 {
     if (ModelState.IsValid)
     {
         var success = _mortgageService.SaveCalculationEntry(entry);
         if (success)
         {
             return(new CustomJson(new CustomJsonModel
             {
                 Success = true,
             }, JsonRequestBehavior.DenyGet));
         }
     }
     return(new CustomJson(new CustomJsonModel
     {
         Success = false,
         Message = _errorMessage
     }, JsonRequestBehavior.DenyGet));
 }