I posted a letter from card svc person at my bank, NationalCity:

Our simplest program would be our phone service. This is just an 800 number that you dial into to get authorization.

The costs associated with this service is 2.63% of the transaction plus .44. For every $100 it would cost you $3.00 a transaction. Visa requires a monthly minimum of $1200 going through the system. If you don't reach that minimum then the fee is charged. At most it would be $18. This $18 is only charged if you have zero sales. The fee is prorated based on the monthly volume. There is also a monthly statement fee of $9.95. This statement shows you all activity and fees associated for the month. The last fee is our implementation fee. This fee is to build your files with us and Visa. This is a one time charge of $175.