When I had a retail location 4 years ago it was $125.00 which eliminated all the stuff that was not our market anyway. Now its $300.00 but we dont have a retail location and are more selective about our work.
If we had a printer and did that sort of work I would think 1 hour should be the minimum - by the time you discuss the project, do a quick design, setup and print I cant see anything taking less than an hour if you count the sales portion which you really should.