diff --git a/src/bonsai/bonsai/tool/cost.py b/src/bonsai/bonsai/tool/cost.py
index 919e649b82..64f8026533 100644
--- a/src/bonsai/bonsai/tool/cost.py
+++ b/src/bonsai/bonsai/tool/cost.py
@@ -568,10 +568,7 @@ class Cost(bonsai.core.tool.Cost):
         import time
 
         start = time.time()
-        csv2ifc = Csv2Ifc()
-        csv2ifc.csv = file_path
-        csv2ifc.file = tool.Ifc.get()
-        csv2ifc.is_schedule_of_rates = is_schedule_of_rates
+        csv2ifc = Csv2Ifc(file_path, tool.Ifc.get(), is_schedule_of_rates=is_schedule_of_rates)
         csv2ifc.execute()
         print("Import finished in {:.2f} seconds".format(time.time() - start))
 
diff --git a/src/ifc5d/README.md b/src/ifc5d/README.md
index c0d7d7f298..8eeee358c8 100644
--- a/src/ifc5d/README.md
+++ b/src/ifc5d/README.md
@@ -36,9 +36,26 @@ E.g. '1', '1.1', '1.1.1', etc.
 E.g. root items of the same level have index '1', their children have '2', etc.
 - 'Index' was preferred for import hierarchy source over 'Hierarchy' as it's easier to edit from the table view.
 
+
+Simple example:
+```python
+import ifc5d.csv2ifc
+
+csv2ifc = ifc5d.csv2ifc.Csv2Ifc(csv_filepath, ifc_file)
+csv2ifc.execute()
+```
+
+
 ## Usage IFC to CSV, ODS, XSLS
 
-#TODO
+Simple example:
+```python
+import ifc5d.ifc5Dspreadsheet
+
+# csv.
+writer = ifc5d.ifc5Dspreadsheet.Ifc5DCsvWriter(ifc_file, temp_csv_dir)
+writer.write()
+```
 
 ### CLI app for converting IFC files to CSV, ODS or XLSX format.
 
diff --git a/src/ifc5d/ifc5d/csv2ifc.py b/src/ifc5d/ifc5d/csv2ifc.py
index 6a04a630e5..27424484af 100644
--- a/src/ifc5d/ifc5d/csv2ifc.py
+++ b/src/ifc5d/ifc5d/csv2ifc.py
@@ -58,11 +58,8 @@ class Csv2Ifc:
     # Inputs.
     csv: str
     file: Union[ifcopenshell.file, None] = None
-    """If not provided, boilerplate file will be created."""
     cost_schedule: Union[ifcopenshell.entity_instance, None] = None
-    """Cost schedule to load cost items to. If not provided, new one will be created."""
     is_schedule_of_rates: bool = False
-    """Whether imported schedule is a schedule of rates."""
 
     # Output.
     cost_items: list[CostItem]
@@ -71,10 +68,33 @@ class Csv2Ifc:
     headers: CsvHeader
     units: dict[str, ifcopenshell.entity_instance]
 
-    def __init__(self):
-        self.units: dict[str, ifcopenshell.entity_instance] = {}
+    def __init__(
+        self,
+        csv: str = None,
+        ifc_file: Union[ifcopenshell.file, None] = None,
+        cost_schedule: Union[ifcopenshell.entity_instance, None] = None,
+        *,
+        is_schedule_of_rates: bool = False,
+    ):
+        """
+        :param csv: CSV filepath to import.
+        :param ifc_file: IFC file to import to. If not provided, boilerplate file will be created.
+        :param cost_schedule: Cost schedule to load cost items to. If not provided, new one will be created.
+        :param is_schedule_of_rates: Whether imported schedule is a schedule of rates.
+        """
+        # TODO: Arguments added only at 25.04.14
+        # `csv` argument is actually not optional, it's only optional for backwards compatibility.
+        # And will be deprecated later.
+        if csv is None:
+            print("WARNING. `csv` argument is not optional and should be provided to the constructor.")
+        self.csv = csv
+        self.file = ifc_file
+        self.cost_schedule = cost_schedule
+        self.is_schedule_of_rates = is_schedule_of_rates
+        self.units = {}
 
     def execute(self) -> None:
+        assert self.csv
         self.parse_csv()
         self.create_ifc()
 
diff --git a/src/ifc5d/ifc5d/ifc5Dspreadsheet.py b/src/ifc5d/ifc5d/ifc5Dspreadsheet.py
index 17d005106b..b44ebb34e3 100644
--- a/src/ifc5d/ifc5d/ifc5Dspreadsheet.py
+++ b/src/ifc5d/ifc5d/ifc5Dspreadsheet.py
@@ -235,9 +235,7 @@ class Ifc5Dwriter:
     # Inputs.
     file: ifcopenshell.file
     output: str
-    """Output filepath."""
     cost_schedule: Union[ifcopenshell.entity_instance, None]
-    """Cost schedule to export. If not provided - export all."""
     colors: dict[int, str]
     """Colors to use for hierarchy indices."""
 
@@ -266,8 +264,9 @@ class Ifc5Dwriter:
         cost_schedule: Optional[ifcopenshell.entity_instance] = None,
     ):
         """
-        Args:
-            cost_schedule: exported cost schedule. If not provided, will export all available schedules.
+        :param file: IFC file to exprot cost schedules from.
+        :param output: Output directory for csv files.
+        :param cost_schedule: exported cost schedule. If not provided, will export all available schedules.
         """
         self.output = output
         if isinstance(file, str):
@@ -277,7 +276,7 @@ class Ifc5Dwriter:
         self.cost_schedule = cost_schedule
         self.colours = self.default_colors.copy()
 
-    def parse(self):
+    def parse(self) -> None:
         """Fill ``sheet_data`` from ``cost_schedules``."""
         self.sheet_data = {}
         counter: Counter[str] = Counter()
@@ -326,13 +325,13 @@ class Ifc5Dwriter:
             attribute = get_position_in_list(attribute, self.sheet_data[schedule_id]["headers"])
             return "{}{}".format(self.column_indexes[attribute], self.row_count)
 
-    def write(self):
+    def write(self) -> None:
         self.cost_schedules = IfcDataGetter.get_schedules(self.file, self.cost_schedule)
         self.parse()
 
 
 class Ifc5DCsvWriter(Ifc5Dwriter):
-    def write(self):
+    def write(self) -> None:
         import csv
 
         super().write()
@@ -348,7 +347,7 @@ class Ifc5DCsvWriter(Ifc5Dwriter):
 
 
 class Ifc5DOdsWriter(Ifc5Dwriter):
-    def write(self):
+    def write(self) -> None:
         from odf.opendocument import OpenDocumentSpreadsheet
         from odf.style import Style, TableCellProperties
         from odf.number import NumberStyle, CurrencyStyle, CurrencySymbol, Number, Text
@@ -465,7 +464,7 @@ class Ifc5DOdsWriter(Ifc5Dwriter):
 
 
 class Ifc5DXlsxWriter(Ifc5Dwriter):
-    def write(self):
+    def write(self) -> None:
         import xlsxwriter
 
         super().write()