Whilst you’re at it, it is time to do all those software updates and ensure your anti-virus subscription and anti-ransomware software is up to date and installed on your phone, tablet, laptop and desktop computers.
By law, security cameras need to be installed by a licensed installer. There are various options including wired, Power over Ethernet and wireless. Some have batteries but most have a wired power supply.
Unless you are very disciplined with recharging batteries, it is inevitable that the very day you need to see footage of a security event will be the very day the batteries run out. In terms of dependability, powered cameras remove the potential for missing a security event on camera due to battery power down.