In the DSUMS you can do this in one recordset for the majority.
' Company.Add "taxblAmtA", Nz(Round(DSum("TaxableValue", "QryJson", "[InvoiceID] =" & Me.txtJsonReceived & "And [TaxClassA] = 'A'"), 4), 0)
' Company.Add "taxblAmtB", Nz(Round(DSum("TaxableValue", "QryJson"...