[gruez]

>2.) guard the IT infrastructure according to the PCI rules (have you ever needed to implement those, especially for small shop owners with no IT know-how)

is this really necessary? AFAIK it's only necessary if you handle credit card numbers, which you don't, and can be outsourced to the payment processor so you're not seeing credit card numbers at all.

>3.) every day/week/month accounting of the payments to the corresponding receipts

this can't be handled by the POS software?

>4.) hope that the customer doesn't initiate a reimbursement

probably not a big issue with card present purchases