diff --git a/common/mhfitem/mhfitem.go b/common/mhfitem/mhfitem.go
index 0249faa34..58fbf45e7 100644
--- a/common/mhfitem/mhfitem.go
+++ b/common/mhfitem/mhfitem.go
@@ -53,6 +53,30 @@ func ReadWarehouseItem(bf *byteframe.ByteFrame) MHFItemStack {
 	return item
 }
 
+func DiffItemStacks(o []MHFItemStack, u []MHFItemStack) []MHFItemStack {
+	// o = old, u = update, f = final
+	var f []MHFItemStack
+	for _, uItem := range u {
+		exists := false
+		for i := range o {
+			if o[i].WarehouseID == uItem.WarehouseID {
+				exists = true
+				o[i].Quantity = uItem.Quantity
+			}
+		}
+		if !exists {
+			uItem.WarehouseID = token.RNG.Uint32()
+			f = append(f, uItem)
+		}
+	}
+	for _, oItem := range o {
+		if oItem.Quantity > 0 {
+			f = append(f, oItem)
+		}
+	}
+	return f
+}
+
 func (is MHFItemStack) ToBytes() []byte {
 	bf := byteframe.NewByteFrame()
 	bf.WriteUint32(is.WarehouseID)
diff --git a/server/channelserver/handlers.go b/server/channelserver/handlers.go
index a3657f7be..fb91f096f 100644
--- a/server/channelserver/handlers.go
+++ b/server/channelserver/handlers.go
@@ -7,7 +7,6 @@ import (
 	"erupe-ce/common/mhfmon"
 	ps "erupe-ce/common/pascalstring"
 	"erupe-ce/common/stringsupport"
-	"erupe-ce/common/token"
 	_config "erupe-ce/config"
 	"fmt"
 	"io"
@@ -844,28 +843,8 @@ func handleMsgMhfEnumerateUnionItem(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgMhfUpdateUnionItem(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfUpdateUnionItem)
-	// o = old, u = update, f = final
-	var fItems []mhfitem.MHFItemStack
-	oItems := userGetItems(s)
-	for _, uItem := range pkt.UpdatedItems {
-		exists := false
-		for i := range oItems {
-			if oItems[i].WarehouseID == uItem.WarehouseID {
-				exists = true
-				oItems[i].Quantity = uItem.Quantity
-			}
-		}
-		if !exists {
-			uItem.WarehouseID = token.RNG.Uint32()
-			fItems = append(fItems, uItem)
-		}
-	}
-	for _, oItem := range oItems {
-		if oItem.Quantity > 0 {
-			fItems = append(fItems, oItem)
-		}
-	}
-	s.server.db.Exec(`UPDATE users u SET item_box=$1 WHERE u.id=(SELECT c.user_id FROM characters c WHERE c.id=$2)`, mhfitem.SerializeWarehouseItems(fItems), s.charID)
+	newStacks := mhfitem.DiffItemStacks(userGetItems(s), pkt.UpdatedItems)
+	s.server.db.Exec(`UPDATE users u SET item_box=$1 WHERE u.id=(SELECT c.user_id FROM characters c WHERE c.id=$2)`, mhfitem.SerializeWarehouseItems(newStacks), s.charID)
 	doAckSimpleSucceed(s, pkt.AckHandle, make([]byte, 4))
 }
 
diff --git a/server/channelserver/handlers_guild.go b/server/channelserver/handlers_guild.go
index 07b9106cb..be61f1241 100644
--- a/server/channelserver/handlers_guild.go
+++ b/server/channelserver/handlers_guild.go
@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"errors"
 	"erupe-ce/common/mhfitem"
-	"erupe-ce/common/token"
 	_config "erupe-ce/config"
 	"fmt"
 	"math"
@@ -1580,28 +1579,8 @@ func handleMsgMhfEnumerateGuildItem(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgMhfUpdateGuildItem(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfUpdateGuildItem)
-	// o = old, u = update, f = final
-	var fItems []mhfitem.MHFItemStack
-	oItems := guildGetItems(s, pkt.GuildID)
-	for _, uItem := range pkt.UpdatedItems {
-		exists := false
-		for i := range oItems {
-			if oItems[i].WarehouseID == uItem.WarehouseID {
-				exists = true
-				oItems[i].Quantity = uItem.Quantity
-			}
-		}
-		if !exists {
-			uItem.WarehouseID = token.RNG.Uint32()
-			fItems = append(fItems, uItem)
-		}
-	}
-	for _, oItem := range oItems {
-		if oItem.Quantity > 0 {
-			fItems = append(fItems, oItem)
-		}
-	}
-	s.server.db.Exec(`UPDATE guilds SET item_box=$1 WHERE id=$2`, mhfitem.SerializeWarehouseItems(fItems), pkt.GuildID)
+	newStacks := mhfitem.DiffItemStacks(guildGetItems(s, pkt.GuildID), pkt.UpdatedItems)
+	s.server.db.Exec(`UPDATE guilds SET item_box=$1 WHERE id=$2`, mhfitem.SerializeWarehouseItems(newStacks), pkt.GuildID)
 	doAckSimpleSucceed(s, pkt.AckHandle, make([]byte, 4))
 }
 
diff --git a/server/channelserver/handlers_house.go b/server/channelserver/handlers_house.go
index 13535791f..705c76393 100644
--- a/server/channelserver/handlers_house.go
+++ b/server/channelserver/handlers_house.go
@@ -495,32 +495,12 @@ func handleMsgMhfEnumerateWarehouse(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgMhfUpdateWarehouse(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfUpdateWarehouse)
-	// o = old, u = update, f = final
-	var fItems []mhfitem.MHFItemStack
-	var fEquip []mhfitem.MHFEquipment
 	switch pkt.BoxType {
 	case 0:
-		oItems := warehouseGetItems(s, pkt.BoxIndex)
-		for _, uItem := range pkt.UpdatedItems {
-			exists := false
-			for i := range oItems {
-				if oItems[i].WarehouseID == uItem.WarehouseID {
-					exists = true
-					oItems[i].Quantity = uItem.Quantity
-				}
-			}
-			if !exists {
-				uItem.WarehouseID = token.RNG.Uint32()
-				fItems = append(fItems, uItem)
-			}
-		}
-		for _, oItem := range oItems {
-			if oItem.Quantity > 0 {
-				fItems = append(fItems, oItem)
-			}
-		}
-		s.server.db.Exec(fmt.Sprintf(`UPDATE warehouse SET item%d=$1 WHERE character_id=$2`, pkt.BoxIndex), mhfitem.SerializeWarehouseItems(fItems), s.charID)
+		newStacks := mhfitem.DiffItemStacks(warehouseGetItems(s, pkt.BoxIndex), pkt.UpdatedItems)
+		s.server.db.Exec(fmt.Sprintf(`UPDATE warehouse SET item%d=$1 WHERE character_id=$2`, pkt.BoxIndex), mhfitem.SerializeWarehouseItems(newStacks), s.charID)
 	case 1:
+		var fEquip []mhfitem.MHFEquipment
 		oEquips := warehouseGetEquipment(s, pkt.BoxIndex)
 		for _, uEquip := range pkt.UpdatedEquipment {
 			exists := false