remove duplicate method and use existing version

app/models/sales_log.rb

@@ -136,10 +136,6 @@ class SalesLog < Log
     type == 18
   end
 
-  def is_older_persons_shared_ownership?
-    type == 24
-  end
-
   def ppostcode_full=(postcode)
     if postcode
       super UKPostcode.parse(postcode).to_s

app/models/validations/sales/financial_validations.rb

@@ -37,7 +37,7 @@ module Validations::Sales::FinancialValidations
   end
 
   def validate_percentage_owned_not_too_much_if_older_person(record)
-    return unless record.is_older_persons_shared_ownership? && record.stairowned
+    return unless record.old_persons_shared_ownership? && record.stairowned
 
     if record.stairowned > 75
       record.errors.add :stairowned, I18n.t("validations.financial.staircasing.older_person_percentage_owned_maximum_75")