Calc: can you combine SUMIF and VLOOKUP?

Ok I have column A1-A32 with a list of different items in them, sometimes identical. On a Different sheet called “Bob” there are cells A1-H32, which contain various data for each type of item some numerical.

I also have the intention of making a Horizontal month to month list (e.g Column A is this month, B will be next month etc), so i can’t utilise the rest of row A for it’s VLOOKUP details and then total each column at the bottom. I really want the sum total of various lookups added as one column, under the list (say, cell A35), and in one cell.

Is it possible to use SUMIF, with a VLOOKUP which takes it’s first argument as being the contents of the cell the sum if is on? If we assume, in the function proposition below, ## represents, for the lookup, the cell the SUMIF function is currently on, I basically am wondering if something like this is possible:

=SUMIF(A1:A32,VLOOKUP(##,$Bob.A1:A32,3,FALSE),<>"")
The <>"" would hopefully make it ignore empty cells as sometimes some cells in the column will be empty.

EDIT: See here for an example, The red cell is where i need the formula and to the side is instructions of what i want to happen.
Example.ods

Not clear to me what’s the meaning of total skill level, the sum of them can be obtained with:
=SUMPRODUCT(SUMIFS(Staff.$B$1:$B$19;Staff.$A$1:$A$19;$B$3:$B$13))
sumproduct is to avoid enter the formula as array, and sumifs because it’s easy to add new criteria if needed.

For average:
=SUMPRODUCT(AVERAGE(IF($B$3:$B$13<>"";AVERAGEIFS(Staff.$C$1:$C$19;Staff.$A$1:$A$19;$B$3:$B$13))))

For sum of average sales:
=SUMPRODUCT(SUMIFS(Staff.$C$1:$C$19;Staff.$A$1:$A$19;$B$3:$B$13))

Attached the file with the formulas
15280559961189898.ods