Ok, that would work, however when I add the "PartsTotalQuery" to the "TotalJobCharge" query, the two of the repairs disappeared because neither of them had a "RepairID" in the "Parts" table that the query was based on...
If I go back to the "PartsTotalQuery", I find only 'RepairID' 2 and 4 in there, as 1 and 3 didn't consist of any parts. So when I add "PartsTotalQuery" to "TotalJobCharge", RepairIDs 1 and 3 disappear and I can't get any totals from them at all!
This is starting to get more complicated than it should be.