Help with power query

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8kstV4hKTVTSUXLMSykC0eb65vpGBkamQKalvpEhiG0JZBuZGgBJQyMQYW4AYhsDRWJ1opW8EgsS84B8p8SsxCzcBhiCDTA2QRhgaGSsFBsLAA==", BinaryEncoding.Base64), Compression.Deflate)), {"ProjectRef", "ModelDataSet", "ProjectStart", "ProjectEnd", "FacilitiesUnitRate", "FacilitiesQuantity", "ServiceUnitRate", "ServiceQuantity"}),    
    ChangeTypes = Table.TransformColumnTypes(Source,{{"ProjectRef", type text}, {"ModelDataSet", type text}, {"ProjectStart", type date}, {"ProjectEnd", type date}, {"FacilitiesUnitRate", Int64.Type}, {"FacilitiesQuantity", Int64.Type}, {"ServiceUnitRate", Int64.Type}, {"ServiceQuantity", Int64.Type}}),
    AddCategoryColumn = Table.AddColumn(ChangeTypes, "Category", each {"Facilities", "Service"}),
    ExpandCategory = Table.ExpandListColumn(AddCategoryColumn, "Category"),
    AddRecordColumn = Table.AddColumn(ExpandCategory, "Custom", each 
        if [Category] = "Facilities" then [Rate = [FacilitiesUnitRate], Quantity = [FacilitiesQuantity]] else [Rate = [ServiceUnitRate], Quantity = [ServiceQuantity]]),
    RemoveColumns = Table.RemoveColumns(AddRecordColumn,{"FacilitiesUnitRate", "FacilitiesQuantity", "ServiceUnitRate", "ServiceQuantity"}),
    Result = Table.ExpandRecordColumn(RemoveColumns, "Custom", {"Rate", "Quantity"})
in
    Result