diff --git a/app/models/validations/sales/sale_information_validations.rb b/app/models/validations/sales/sale_information_validations.rb
index c70a8d57d..be0295f2c 100644
--- a/app/models/validations/sales/sale_information_validations.rb
+++ b/app/models/validations/sales/sale_information_validations.rb
@@ -1,5 +1,5 @@
 module Validations::Sales::SaleInformationValidations
-  def validate_pratical_completion_date_before_saledate(record)
+  def validate_practical_completion_date_before_saledate(record)
     return if record.saledate.blank? || record.hodate.blank?
 
     unless record.saledate > record.hodate
@@ -7,6 +7,19 @@ module Validations::Sales::SaleInformationValidations
     end
   end
 
+  def validate_years_living_in_property_before_purchase(record)
+    return unless record.proplen && record.proplen.nonzero?
+
+    case record.type
+    when 18
+      record.errors.add :type, I18n.t("validations.sale_information.proplen.social_homebuy")
+      record.errors.add :proplen, I18n.t("validations.sale_information.proplen.social_homebuy")
+    when 28, 29
+      record.errors.add :type, I18n.t("validations.sale_information.proplen.rent_to_buy")
+      record.errors.add :proplen, I18n.t("validations.sale_information.proplen.rent_to_buy")
+    end
+  end
+
   def validate_exchange_date(record)
     return unless record.exdate && record.saledate
 
diff --git a/config/locales/en.yml b/config/locales/en.yml
index cdad12a52..c988d2dd9 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -413,6 +413,9 @@ en:
       deactivation:
         during_deactivated_period: "The location is already deactivated during this date, please enter a different date"
     sale_information:
+      proplen:
+        social_homebuy: "Social HomeBuy buyers should not have lived here before"
+        rent_to_buy: "Rent to Buy buyers should not have lived here before"
       exdate:
         must_be_before_saledate:
           Contract exchange date must be less than 1 year before completion date
diff --git a/spec/models/validations/sales/sale_information_validations_spec.rb b/spec/models/validations/sales/sale_information_validations_spec.rb
index 409972040..fb3aea06c 100644
--- a/spec/models/validations/sales/sale_information_validations_spec.rb
+++ b/spec/models/validations/sales/sale_information_validations_spec.rb
@@ -5,12 +5,12 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
 
   let(:validator_class) { Class.new { include Validations::Sales::SaleInformationValidations } }
 
-  describe "#validate_pratical_completion_date_before_saledate" do
+  describe "#validate_practical_completion_date_before_saledate" do
     context "when hodate blank" do
       let(:record) { build(:sales_log, hodate: nil) }
 
       it "does not add an error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors).not_to be_present
       end
@@ -20,7 +20,7 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       let(:record) { build(:sales_log, saledate: nil) }
 
       it "does not add an error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors).not_to be_present
       end
@@ -30,7 +30,7 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       let(:record) { build(:sales_log, hodate: nil, saledate: nil) }
 
       it "does not add an error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors).not_to be_present
       end
@@ -40,7 +40,7 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       let(:record) { build(:sales_log, hodate: 2.months.ago, saledate: 1.month.ago) }
 
       it "does not add the error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors).not_to be_present
       end
@@ -50,7 +50,7 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       let(:record) { build(:sales_log, hodate: 1.month.ago, saledate: 2.months.ago) }
 
       it "adds error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors[:hodate]).to be_present
       end
@@ -60,7 +60,7 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       let(:record) { build(:sales_log, hodate: Time.zone.parse("2023-07-01"), saledate: Time.zone.parse("2023-07-01")) }
 
       it "does not add an error" do
-        sale_information_validator.validate_pratical_completion_date_before_saledate(record)
+        sale_information_validator.validate_practical_completion_date_before_saledate(record)
 
         expect(record.errors[:hodate]).to be_present
       end
@@ -164,4 +164,58 @@ RSpec.describe Validations::Sales::SaleInformationValidations do
       end
     end
   end
+
+  describe "#validate_years_living_in_property_before_purchase" do
+    context "when proplen blank" do
+      let(:record) { build(:sales_log, proplen: nil) }
+
+      it "does not add an error" do
+        sale_information_validator.validate_years_living_in_property_before_purchase(record)
+
+        expect(record.errors).not_to be_present
+      end
+    end
+
+    context "when type blank" do
+      let(:record) { build(:sales_log, type: nil) }
+
+      it "does not add an error" do
+        sale_information_validator.validate_years_living_in_property_before_purchase(record)
+
+        expect(record.errors).not_to be_present
+      end
+    end
+
+    context "when proplen 0" do
+      let(:record) { build(:sales_log, proplen: 0) }
+
+      it "does not add an error" do
+        sale_information_validator.validate_years_living_in_property_before_purchase(record)
+
+        expect(record.errors).not_to be_present
+      end
+    end
+
+    context "when type Rent to Buy and proplen > 0" do
+      let(:record) { build(:sales_log, proplen: 1, type: 28) }
+
+      it "adds an error" do
+        sale_information_validator.validate_years_living_in_property_before_purchase(record)
+
+        expect(record.errors[:type]).to include(I18n.t("validations.sale_information.proplen.rent_to_buy"))
+        expect(record.errors[:proplen]).to include(I18n.t("validations.sale_information.proplen.rent_to_buy"))
+      end
+    end
+
+    context "when type Social HomeBuy and proplen > 0" do
+      let(:record) { build(:sales_log, proplen: 1, type: 18) }
+
+      it "adds an error" do
+        sale_information_validator.validate_years_living_in_property_before_purchase(record)
+
+        expect(record.errors[:type]).to include(I18n.t("validations.sale_information.proplen.social_homebuy"))
+        expect(record.errors[:proplen]).to include(I18n.t("validations.sale_information.proplen.social_homebuy"))
+      end
+    end
+  end
 end