pci compliance for very small biz using mac and ipad

For the iPad and iPhone, Apple checks out the software before putting it in the store.

Most of the so called anti-virus software checkers on the Mac are a scam and are worse than not using such software. The best only check for Windows problems in your email. The net is do not use an anti-virus software on the mac.

What to do? Stay current on your software updates. That is every quarter verify that you have the latest software update from Apple. Apple includes malware detection and malware removal software within Mac OS. By being up-to-date on the OS, you have run the latest malware detection software.

You have a Mac therefor you are are availing all the malware problems of Windows.

Anti-virus software would not do PCI vulnerability scanning. You need specialized software to do that. Unfortunately, I cannot recommend specific software. My wife's small business was wrestling with PCI issues some time ago, and they're currently not doing any kind of internal scans. I don't know why not. They do get scanned externally periodically, to look for vulnerabilities in their setup that could allow people outside their network to gain access.

PCI compliance is a scam anyway. It doesn't prevent the numerous breaches that so many high-profile companies have been facing lately, and you can bet they're dotting their i's and crossing their t's with respect to PCI compliance. They have the budget to do so.

Your Mac should not need the firewall on. That shouldn't affect PCI compliance, if the Mac is properly configured and does not have any services open in System Preferences -> Sharing.

Read this discussion. It should help you. Vulnerability Scan Software

Firstly, anti-malware software would not be appropriate to use. I doubt seriously that you need to do anything but be sure you keep your local network secure.