Looked at your other posts, an online / virtual terminal is what you need.
Payzone is probably best option in that they are part of aib and deal with small business.
No monthly costs and circa 1%- 2% commission (depends on card type - business cards are about 1% premium to standard cards, if cardholder is not present an additional small commission applies.
If the customer is present and you use a physical terminal, the commission rate is from 0.2% (debit cards)
I did check an post and their rates were a little on the high side for me - more suited to smaller users who wanted a terminal.