I do not know how tech savvy you are, but we use this and are extremely happy with it:
https://www.phreesoft.com/ It does require that you:
1) Know linux and can maintain it
2) Know how to install things on a "LAMP" stack
Once it's installed, it's pretty bullet proof. You access it from a web browser so your accounting info is anywhere you need it to be. If you do go this route I'd recommend you use SSL (just like your bank). If you need any help getting it up and running let me know, I can give you some tips/pointers.
If you want something that is more point-click-done, then QuickBooks is your solution. Considering they make everything for it, I am sure there is a POS and CC Gateway out there for you. I have used it and I didn't care for how it managed it's accounting, but to each their own.
