Contact first. A lighter tool which doesn't suit the surface hasn't saved anything. Then I'd look at whether I can make the suitable arrangement smaller.
I'd put access for maintenance on the comparison too. Can the person looking after it identify and replace the contact elements without rebuilding the whole experiment?
That gives me a better quote request: same sample boxes, actual assembled mass and replacement contact parts priced separately. Otherwise I'd probably compare two totals and miss why they differ.
