Costs very widely based on what you are
looking to do, who you want to do it,
and what format you want it in.
project is different.
you need lights, seperate audio person,
wireless mics, tripod, dolly, etc.
best option is to put together what you
want to have done then call around to
different video companies.
kid with a video camera might work for
minimum wage while a production company
could ask for $100-$10000 an hour depending
on what your needs are.