Hi,

Better you need an UDF as there are cells having multiple 'OBS' to look.

Code:
Function PAREDES(ByRef LookupValue, ByRef LookupTable As Range, ByVal ColIdx As Long) As Double

    
    Dim TblAry      As String, x, i As Long
    
    If TypeOf LookupValue Is Range Then LookupValue = LookupValue.Value2
    
    TblAry = "'" & LookupTable.Parent.Name & "'!" & LookupTable.Address
    
    x = Split(LookupValue, ",")
    
    For i = 0 To UBound(x)
        PAREDES = PAREDES + Evaluate("vlookup(""" & Trim$(x(i)) & """," & TblAry & "," & ColIdx & ",0)")
    Next
    
End Function
How to use this UDF.

Copy this code > Open the workbook > Hit Alt + F11 > Go to Insert > Module and paste the code. Now hit Alt + Q to close the VBE window.

In F10:

=(D10*E10)-PAREDES(A10,$H$3:$L$14,5)

copy the formula in F23

HTH