diff --git a/src/paysgator/client.py b/src/paysgator/client.py
index a067367..5cb7703 100644
--- a/src/paysgator/client.py
+++ b/src/paysgator/client.py
@@ -53,6 +53,8 @@ class PaysgatorClient:
     BASE_URL = "https://paysgator.com/api/v1"
 
     def __init__(self, api_key: str):
+        if not api_key or not isinstance(api_key, str) or len(api_key.strip()) < 10:
+            raise ValueError("API key must be a non-empty string with at least 10 characters")
         self.api_key = api_key
         self.session = requests.Session()
         self.session.headers.update({
@@ -70,7 +72,7 @@ def set_base_url(self, url: str):
 
     def request(self, method: str, endpoint: str, data: Optional[dict] = None) -> dict:
         url = f"{self.BASE_URL}{endpoint}"
-        response = self.session.request(method, url, json=data)
+        response = self.session.request(method, url, json=data, timeout=30)
         
         if response.status_code >= 400:
              raise APIError(response.status_code, response.text)
diff --git a/src/paysgator/exceptions.py b/src/paysgator/exceptions.py
index 3067741..bab806a 100644
--- a/src/paysgator/exceptions.py
+++ b/src/paysgator/exceptions.py
@@ -8,7 +8,7 @@ class AuthenticationError(PaysgatorError):
 
 class APIError(PaysgatorError):
     """Raised when the API returns an error"""
-    def __init__(self, status_code: int, message: str):
+    def __init__(self, status_code: int, message: str, *args, **kwargs):
         self.status_code = status_code
         self.message = message
         super().__init__(f"API Error {status_code}: {message}")
diff --git a/src/paysgator/models.py b/src/paysgator/models.py
index 8863e2d..2f7bf1c 100644
--- a/src/paysgator/models.py
+++ b/src/paysgator/models.py
@@ -73,5 +73,5 @@ class TransactionResponse(BaseModel):
 class WalletBalanceResponse(BaseModel):
     wallet_id: str = Field(..., alias="walletId")
     currency: str
-    balance: str
+    balance: float
     mode: str
diff --git a/test_sdk.py b/test_sdk.py
index 7ee8b76..c22bbdd 100644
--- a/test_sdk.py
+++ b/test_sdk.py
@@ -1,10 +1,11 @@
+import os
 from src.paysgator.client import PaysgatorClient
 
 #Mpesa direct charge test 
 
-api_key = "<Api Key>"
+api_key = os.getenv("PAYSGATOR_API_KEY", "<Api Key>")
 
-wallet_id = "<Wallet Id>"
+wallet_id = os.getenv("PAYSGATOR_WALLET_ID", "<Wallet Id>")
 
 client = PaysgatorClient(api_key, wallet_id)