diff --git a/post_frame.lua b/post_frame.lua
index 55788b9..780218c 100644
--- a/post_frame.lua
+++ b/post_frame.lua
@@ -483,8 +483,8 @@ function public.on_load()
         btn:GetFontString():SetJustifyH('RIGHT')
         btn:GetFontString():SetPoint('RIGHT', 0, 0)
         btn:SetScript('OnClick', function()
-            private.set_unit_start_price(this.amount)
-            private.set_unit_buyout_price(this.amount)
+            private.set_unit_start_price(this.amount or 0)
+            private.set_unit_buyout_price(this.amount or 0)
         end)
         local label = Aux.gui.label(btn, 13)
         label:SetPoint('BOTTOMLEFT', btn, 'TOPLEFT', -2, 1)