C is for cost...
...cost 💵😱
If security software sounds expensive the following might help:
Like anything - security software has sales! Where you see sales on at the shops - start to check out which security providers may also have a sale - often you can get a good discount or a longer period of coverage. Don't however "wait" for the sales to get coverage - and don't forget to ensure you have security software on all your devices (tablets and phones as well as PCs).