diff --git a/ffxiahbot/auction/manager.py b/ffxiahbot/auction/manager.py
index 7d5f68f..2889c2d 100644
--- a/ffxiahbot/auction/manager.py
+++ b/ffxiahbot/auction/manager.py
@@ -185,6 +185,11 @@ def _buy_row(self, row: AuctionHouse, max_price: int) -> bool:
             row: Auction House row to buy.
             max_price: Maximum price to pay.
         """
+        if max_price <= 0:
+            logger.error("max buying price is zero! itemid=%d", row.itemid)
+            self.add_to_blacklist(row.id)
+            return False
+
         # check price
         if row.price <= max_price:
             date = timeutils.timestamp(datetime.datetime.now())