really depends on the size of the pad. i have done some that are 4" x 6" and up to 9" x 14".
the larger one is basically the same size as a small solo seat.
i myself don't charge extra for tooling so if they want it plain, they are loosing out. i hate plain seats but, that just me
i know i don't charge near enough and generally i charge less for a p-pad because it is being done with the seat but, i have done them for as little as $50 and up to $225
here are three that i have done.
all different sizes.
BTW i do find them more difficult to cover than a seat. i guess there is just less room for error