diff --git a/src/__init__.py b/src/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/models.py b/src/models.py
index f4f6009..c8e1657 100644
--- a/src/models.py
+++ b/src/models.py
@@ -2,18 +2,81 @@
 
 from datetime import date
 from decimal import Decimal
+from enum import Enum
 
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, Field, ValidationError, field_validator
 
 IBAN_PATTERN = r"^[A-Z]{2}\d{2}[A-Z0-9]{11,30}$"
 
 
+class Currency(str, Enum):
+    EUR = "EUR"
+    USD = "USD"
+    GBP = "GBP"
+    CHF = "CHF"
+
+
+class AmountType(str, Enum):
+    DBIT = "DBIT"
+    CRDT = "CRDT"
+
+    @property
+    def sign(self) -> int:
+        return -1 if self == self.DBIT else +1
+
+
 class B4wExport(BaseModel):
     id: int = Field(alias="Id1", description="internal B4w ID")
     account_iban: str = Field(alias="OwnrAcctIBAN", pattern=IBAN_PATTERN)
+    account_currency: Currency = Field(alias="OwnrAcctCcy")
     date_valid: date = Field(alias="ValDt")
     amount: Decimal = Field(alias="Amt")
+    amount_currency: Currency = Field(alias="AmtCcy")
+    amount_type: AmountType = Field(alias="CdtDbtInd")
+    reference: str = Field(alias = "RmtInf")
+    other_name: str = Field(alias = "RmtdNm")
+    other_iban: str = Field(alias = "RmtdAcctIBAN")
+    category: Category | None = Field(alias = "Category")
+    notes: str = Field(alias = "Notes")
+
+
+    @property
+    def amount_signed(self) -> Decimal:
+        return self.amount * self.amount_type.sign
+
+    @field_validator("category", mode="before")
+    @classmethod
+    def category_str_is_parsable(cls, category_str: str) -> Category | None:
+        category = Category.from_str(category_str)
+        assert category
+        category_str_2 = category.to_str()
+        if not category_str == category_str_2:
+            raise ValidationError(f"Category string cannot be parsed: {category_str}")
+        return category
+
+
+
+class Category(BaseModel):
+    name: str = Field(pattern=r"[^:\r\n]+")
+    parent: Category | None = None
 
     @classmethod
-    def from_dict(cls, d: dict) -> B4wExport:
-        return cls.model_validate(d)
+    def from_str(cls, s: str) -> Category | None:
+        if not s:
+            return
+        components = s.split(":")
+        name = components[-1]
+        rest = ":".join(components[:-1])
+        return cls(name=name, parent=cls.from_str(rest))
+
+    def to_str(self) -> str | None:
+        if not self.parent:
+            return self.name
+        else:
+            return f"{self.parent.to_str()}:{self.name}"
+
+    def __str__(self):
+        return self.to_str()
+
+    def __repr__(self):
+        return f"Category.from_str(\"{self.__str__()}\")"
diff --git a/src/reader.py b/src/reader.py
index 39a3ae2..9eaaa18 100644
--- a/src/reader.py
+++ b/src/reader.py
@@ -11,9 +11,7 @@ def reader_raw(path: Path):
     with path.open() as fid:
         return list(csv.DictReader(fid))
 
+
 def reader_b4w(path: Path):
     raw = reader_raw(path)
-    return list(map(B4wExport.from_dict, raw))
-
-
-
+    return list(map(B4wExport.model_validate, raw))