Try this out (its the answer to both your questions ) -
 With sourceData
            .Range("C10:X" & .Range("C48").End(xlUp).Row).Copy
Master.Worksheets(1).Range("C" & Master.Worksheets(1).Rows.Count).End(xlUp).Offset(1, 0).pastespecial, paste:=xlpastevalues
        End With