If you replace the ddOCost & ddWCost dropdowns with text formfields of the same name, your two macros could be reduced to:
Code:
Sub PopulatedCosts()
Dim ddOCost As String, ddWCost As String
With ActiveDocument
Select Case .FormFields("ddSize").Result
Case "20kW": ddOCost = "$993.00": ddWCost = "$1,568.00"
Case "56kW": ddOCost = "$1,471.00": ddWCost = "$2,046.00"
Case "100kW": ddOCost = "$1,759.00": ddWCost = "$2,334.00"
Case "125kW": ddOCost = "$2,220.00": ddWCost = "$2,795.00"
Case "150kW": ddOCost = "$2,322.00": ddWCost = "$2,897.00"
Case "175kW": ddOCost = "$2,322.00": ddWCost = "$2,897.00"
Case "200kW": ddOCost = "$2,890.00": ddWCost = "$3,465.00"
Case "250kW": ddOCost = "$3,561.00": ddWCost = "$4,136.00"
Case "300kW": ddOCost = "$4,821.00": ddWCost = "$5,396.00"
Case "350kW": ddOCost = "$5,760.00": ddWCost = "$6,335.00"
Case "400kW": ddOCost = "$5,510.00": ddWCost = "$6,085.00"
Case "450kW": ddOCost = "$5,980.00": ddWCost = "$6,555.00"
Case "500kW": ddOCost = "$7,201.00": ddWCost = "$7,776.00"
Case "650kW": ddOCost = "$7,817.00": ddWCost = "$8,392.00"
Case "700kW": ddOCost = "$6,770.00": ddWCost = "$7,345.00"
Case "750kW": ddOCost = "$10,370.00": ddWCost = "$10,945.00"
Case "800kW": ddOCost = "$10,656.00": ddWCost = "$11,231.00"
Case "900kW": ddOCost = "$10,969.00": ddWCost = "$11,544.00"
Case "1,000kW": ddOCost = "$13,495.00": ddWCost = "$14,070.00"
Case "1,250kW": ddOCost = "$14,951.00": ddWCost = "$15,526.00"
Case "1,500kW": ddOCost = "$19,753.00": ddWCost = "$20,328.00"
Case "2,000kW": ddOCost = "$24,269.00": ddWCost = "$24,844.00"
Case Else: ddOCost = "": ddWCost = ""
End Select
.FormFields("ddOCost").Result = ddOCost
.FormFields("ddWCost").Result = ddWCost
End With
End Sub
PS: You might want to check whether you have the right costings for the 350kW, 400kW, 650kW & 700kW entries.