Ours is around £25 a month for terminal rental/service then card charges depend on what cards are used. Debit cards used to be a single 18p per transaction regardless of amount but that was changed to a percentage of sale a few years back. Still cheaper to process than credit cards. Business/commercial Credit cards are as much as 3% and given that bloody E.U. legislation stopped companies adding a surcharge for credit cards last year Those folks that think they're getting "rewards" or money back for using high cost cards are forcing retailers on low margins to push prices up for everyone.
That said over the last 5 to 10 years the vast majority of transactions we put through are payments by visa debit so it's not too bad.
Paypal card payments is around 3% + a 35p (I think) charge per transaction so an expecnsive way of taking payments.