diff --git a/etl/epc/property_change_app.py b/etl/epc/property_change_app.py
index 0f425906..471fe7b0 100644
--- a/etl/epc/property_change_app.py
+++ b/etl/epc/property_change_app.py
@@ -397,16 +397,57 @@ def compare_records(earliest_record: pd.Series, latest_record: pd.Series, column
     if all_equal:
         return True
 
+from dataclasses import dataclass
+@dataclass
 class EPCRecord:
     """
     Base class for a EPC record
     """
+    WALLS_DESCRIPTION: str
+    FLOOR_DESCRIPTION: str
+    LIGHTING_DESCRIPTION: str
+    ROOF_DESCRIPTION: str
+    MAINHEAT_DESCRIPTION: str
+    HOTWATER_DESCRIPTION: str
+    MAIN_FUEL: str
+    MECHANICAL_VENTILATION: str
+    SECONDHEAT_DESCRIPTION: str
+    WINDOWS_DESCRIPTION: str
+    GLAZED_TYPE: str
+    MULTI_GLAZE_PROPORTION: float
+    LOW_ENERGY_LIGHTING: float
+    NUMBER_OPEN_FIREPLACES: float
+    MAINHEATCONT_DESCRIPTION: str
+    SOLAR_WATER_HEATING_FLAG: str
+    PHOTO_SUPPLY: float
+    TRANSACTION_TYPE: str
+    ENERGY_TARIFF: str
+    EXTENSION_COUNT: float
+    TOTAL_FLOOR_AREA: float
+    FLOOR_HEIGHT: float
+    HOT_WATER_ENERGY_EFF: str
+    FLOOR_ENERGY_EFF: str
+    WINDOWS_ENERGY_EFF: str 
+    WALLS_ENERGY_EFF: str
+    SHEATING_ENERGY_EFF: str
+    ROOF_ENERGY_EFF: str
+    MAINHEAT_ENERGY_EFF: str
+    MAINHEATC_ENERGY_EFF: str 
+    LIGHTING_ENERGY_EFF: str
+    POTENTIAL_ENERGY_EFFICIENCY: float
+    ENVIRONMENT_IMPACT_POTENTIAL: float
+    ENERGY_CONSUMPTION_POTENTIAL: float 
+    CO2_EMISSIONS_POTENTIAL: float
+    LODGEMENT_DATE: str
+    CURRENT_ENERGY_EFFICIENCY: int
+    ENERGY_CONSUMPTION_CURRENT: int
+    CO2_EMISSIONS_CURRENT: float
 
-    def __init__(self, num) -> None:
-        self.num = num
+    # def __init__(self, num) -> None:
+    #     self.num = num
 
-    def __sub__(self, other: EPCRecord):
-        return self.num - other.num
+    # def __sub__(self, other):
+    #     return self.num - other.num
     
 
 test = EPCRecord(10)
@@ -475,7 +516,7 @@ def app():
             # e.g. first vs second, second vs third and also first vs third
             property_model_data = []
             for idx in range(0, property_data.shape[0] - 1):
-
+                
                 if idx >= property_data.shape[0] - 1:
                     break