A 16-port unmanaged switch such as this one from TP-Link should run you $50 or $60, while a 24-port unmanaged switch like this one from Netgear typically costs between $70 and $90.

Top-down view of the US-8-150W against the US-24-250W. The 8-port switch is longer front-to-back than a typical desktop switch, but not as long as the rackmount 24-port version.

This is a 24-port switch designed for smart network deployments that utilise PoE technology to simplify and easily adapt the cable infrastructure.

PoE (or IEEE802.3af as it's easily referred to as) is simply slower than PoE+ (IEEE802.3at) and caps out at 15W per port, while PoE+ pushes this up to around 30W per port.