I used this little cube for calculating my filament prices on 3DHubs.com. With the density and price of the filament of your vendor you can calculate the prices for your 3DHubs prints.
According to 3DHubs the prices you provide should include "25% infill, 0.8mm wall thickness and no support". This cube is exactly 1cm³ and therefore let's you calculate your prices easily. Slice it with your favorite slicer software with the appropriate parameters, calculate your price based on your filaments specifications.

Prusa

Prusa Mk2

No

No

as desired

25%