Best Table Layout

I need to visually compare the costs of 4 products that are currently in 4
tables of data, each table on its own worksheet.

Each table contains the following columns:
Number of Employees (1 to 100)
Core Application (cost in dollars)
Module 1 (cost in dollars)
Module 2 (cost in dollars)
Module 3 (cost in dollars)
Documentation (cost in dollars)

I'm thinking that I may need to also add a Total column to sum costs in each
row.

I'd like to graph the number of employees on the x-axis and the cost on the
y-axis, and have each product in its onw series showing how the costs rise
and plateau across the number of employees.

I think that ideally it would be good to have the graph as a pivot chart so
that I could dynamically select which fields are graphed.

What I can't work out is how to best layout the tables so that I can graph
each product in its own series (ie. have 4 series) and then be able to also
select from a dropdown which fields are included (ie. all fields, just
documentation, all fields except module 3, etc). I thought the Pivot Chart
with Multiple Consolidated Ranges would be my best bet, but it results in one
(consolidated) series that I can't seem to split out into the 4 products.

It seems like I have a 3d cube of data. Should I try and mangle this into
one table somehow and then graph the fields in this one table, or should I
persevere with the current structure?

What's the best approach?

TIA.