diff --git a/costs/cost.py b/costs/cost.py
index 9780e41..5911236 100644
--- a/costs/cost.py
+++ b/costs/cost.py
@@ -98,6 +98,7 @@ class Cost:
         global_capital_costs['D5020_lighting_and_branch_wiring'] +
         global_capital_costs['D301010_photovoltaic_system']
     )
+
     df_end_of_life_costs = global_end_of_life_costs['End_of_life_costs']
     df_operational_costs = (
         global_operational_costs['Fixed_costs_electricity_peak'] +
diff --git a/tests/unit_tests.py b/tests/unit_tests.py
index 5a6b1dd..64f2140 100644
--- a/tests/unit_tests.py
+++ b/tests/unit_tests.py
@@ -18,53 +18,64 @@ from costs.cost import Cost
 from costs.constants import SKIN_RETROFIT, SKIN_RETROFIT_AND_SYSTEM_RETROFIT_AND_PV, SYSTEM_RETROFIT_AND_PV
 
 
+class Initialize:
+  def __init__(self):
+    self._city = None
+
+  @property
+  def city(self):
+    if self._city is None:
+      print('init tests')
+      city_file = (Path(__file__).parent / 'data/test.geojson').resolve()
+      output_path = (Path(__file__).parent / 'output').resolve()
+      city = GeometryFactory('geojson',
+                             city_file,
+                             height_field='citygml_me',
+                             year_of_construction_field='ANNEE_CONS',
+                             function_field='CODE_UTILI',
+                             function_to_hub=Dictionaries().montreal_function_to_hub_function).city
+      ConstructionFactory('nrcan', city).enrich()
+      UsageFactory('nrcan', city).enrich()
+      ExportsFactory('sra', city, output_path).export()
+      sra_file = str((output_path / f'{city.name}_sra.xml').resolve())
+      subprocess.run(['sra', sra_file], stdout=subprocess.DEVNULL)
+      ResultFactory('sra', city, output_path).enrich()
+
+      for building in city.buildings:
+        building.energy_systems_archetype_name = 'system 1 gas pv'
+      EnergySystemsFactory('montreal_custom', city).enrich()
+      EnergyBuildingsExportsFactory('insel_monthly_energy_balance', city, output_path).export()
+      _insel_files = glob.glob(f'{output_path}/*.insel')
+      for insel_file in _insel_files:
+        subprocess.run(['insel', str(insel_file)], stdout=subprocess.DEVNULL)
+      ResultFactory('insel_monthly_energy_balance', city, output_path).enrich()
+      self._city = city
+      print('init completed')
+    return self._city
+
+
 class UnitTests(unittest.TestCase):
-  def setUp(self) -> None:
-
-    city_file = (Path(__file__).parent / 'data/test.geojson').resolve()
-    output_path = (Path(__file__).parent / 'output').resolve()
-    city = GeometryFactory('geojson',
-                           city_file,
-                           height_field='citygml_me',
-                           year_of_construction_field='ANNEE_CONS',
-                           function_field='CODE_UTILI',
-                           function_to_hub=Dictionaries().montreal_function_to_hub_function).city
-    ConstructionFactory('nrcan', city).enrich()
-    UsageFactory('nrcan', city).enrich()
-    ExportsFactory('sra', city, output_path).export()
-    sra_file = str((output_path / f'{city.name}_sra.xml').resolve())
-    subprocess.run(['sra', sra_file])
-    ResultFactory('sra', city, output_path).enrich()
-
-    for building in city.buildings:
-      building.energy_systems_archetype_name = 'system 1 gas pv'
-    EnergySystemsFactory('montreal_custom', city).enrich()
-    EnergyBuildingsExportsFactory('insel_monthly_energy_balance', city, output_path).export()
-    _insel_files = glob.glob(f'{output_path}/*.insel')
-    for insel_file in _insel_files:
-      subprocess.run(['insel', str(insel_file)], stdout=subprocess.DEVNULL)
-    ResultFactory('insel_monthly_energy_balance', city, output_path).enrich()
-    self._city = city
+  init = Initialize()
 
   def test_current_status(self):
-    for building in self._city.buildings:
+    for building in self.init.city.buildings:
       result = Cost(building).life_cycle
       self.assertIsNotNone(result)
       self.assertEqual(0, result.values[0])
 
   def test_scenario_1(self):
-    for building in self._city.buildings:
+    for building in self.init.city.buildings:
       result = Cost(building, retrofit_scenario=SKIN_RETROFIT).life_cycle
       self.assertIsNotNone(result)
 
   def test_scenario_2(self):
-    for building in self._city.buildings:
+    for building in self.init.city.buildings:
       result = Cost(building, retrofit_scenario=SYSTEM_RETROFIT_AND_PV).life_cycle
       self.assertIsNotNone(result)
       self.assertEqual(0, result.values[0])
 
   def test_scenario_3(self):
-    for building in self._city.buildings:
+    for building in self.init.city.buildings:
       result = Cost(building, retrofit_scenario=SKIN_RETROFIT_AND_SYSTEM_RETROFIT_AND_PV).life_cycle
       self.assertIsNotNone(result)