Things to consider…
1 How many licences?
> If you have more than one Mac in your household, most antivirus developers offer multi-device licenses at a heavy discount.
2 Renewal costs
> The vast majority of antivirus tools offer a discounted price for your first year of protection. Just be prepared for a hike in premiums once you start paying for subsequent years.
3 Add a firewall
> Your Mac’s built-in firewall only blocks threats that originate on the internet; but third-party firewalls can work in both directions, blocking malware from ‘dialing home’ to do more damage to your Mac.
4 More comprehensive protection
> Many security products also offer security suites covering all aspects of your Mac’s privacy and security, along with extras like system optimisation.