I figured it out. For every line that the inventory was returning, it had an entry for the WIP parts. The example that I showed had 4 entries for inventory parts and 1 for wip, so on all 4 of the lines it was returning a 1 for the WIP parts which added 3 parts. I had to write sub queries to get the totals for the Inventory parts to unique lines and another for the WIP totals to be on unique lines. Then on the top query add the two tables. Below is my final query that works. I might not need the "isnull" on both levels, but I just left if in there since it seems to work with it.
select
[WhseBin].[WarehouseCode] as [WhseBin_WarehouseCode],
[WhseBin].[BinNum] as [WhseBin_BinNum],
(sum(isnull(SubQuery2.Calculated_BinTotalParts,0))+sum(isnull(SubQuery3.Calculated_WipTotal,0))) as [Calculated_TotalBin]
from Erp.WhseBin as WhseBin
left outer join (select
[PartBin].[WarehouseCode] as [PartBin_WarehouseCode],
[PartBin].[BinNum] as [PartBin_BinNum],
(sum ( isnull(PartBin.OnhandQty,0))) as [Calculated_BinTotalParts]
from Erp.PartBin as PartBin
group by [PartBin].[WarehouseCode],
[PartBin].[BinNum]) as SubQuery2 on
WhseBin.WarehouseCode = SubQuery2.PartBin_WarehouseCode
And
WhseBin.BinNum = SubQuery2.PartBin_BinNum
left outer join (select
[PartWip].[WareHouseCode] as [PartWip_WareHouseCode],
[PartWip].[BinNum] as [PartWip_BinNum],
(sum(isnull(PartWip.Quantity,0))) as [Calculated_WipTotal]
from Erp.PartWip as PartWip
group by [PartWip].[WareHouseCode],
[PartWip].[BinNum]) as SubQuery3 on
WhseBin.WarehouseCode = SubQuery3.PartWip_WareHouseCode
And
WhseBin.BinNum = SubQuery3.PartWip_BinNum
group by [WhseBin].[WarehouseCode],
[WhseBin].[BinNum]
select
[WhseBin].[WarehouseCode] as [WhseBin_WarehouseCode],
[WhseBin].[BinNum] as [WhseBin_BinNum],
(sum(isnull(SubQuery2.Calculated_BinTotalParts,0))+sum(isnull(SubQuery3.Calculated_WipTotal,0))) as [Calculated_TotalBin]
from Erp.WhseBin as WhseBin
left outer join (select
[PartBin].[WarehouseCode] as [PartBin_WarehouseCode],
[PartBin].[BinNum] as [PartBin_BinNum],
(sum ( isnull(PartBin.OnhandQty,0))) as [Calculated_BinTotalParts]
from Erp.PartBin as PartBin
group by [PartBin].[WarehouseCode],
[PartBin].[BinNum]) as SubQuery2 on
WhseBin.WarehouseCode = SubQuery2.PartBin_WarehouseCode
And
WhseBin.BinNum = SubQuery2.PartBin_BinNum
left outer join (select
[PartWip].[WareHouseCode] as [PartWip_WareHouseCode],
[PartWip].[BinNum] as [PartWip_BinNum],
(sum(isnull(PartWip.Quantity,0))) as [Calculated_WipTotal]
from Erp.PartWip as PartWip
group by [PartWip].[WareHouseCode],
[PartWip].[BinNum]) as SubQuery3 on
WhseBin.WarehouseCode = SubQuery3.PartWip_WareHouseCode
And
WhseBin.BinNum = SubQuery3.PartWip_BinNum
group by [WhseBin].[WarehouseCode],
[WhseBin].[BinNum]