Even the most expensive configuration will be cheaper than a $500 commercial IP-KVM. Easy to build - For the V1 variant There are many ways to build a PiKVM. Video capture devices can be attached ...
The only downside is that they can get pricey, unless of course you can roll one out based on the Raspberry Pi and the PiKVM image for little more than the cost of the Pi itself. The video linked ...
When talking about PiKVM and GPIO it refers not solely to the physical interface ... note "Click to view" The extron plugin allows you to control Extron SW series switchers (ex. SW4 USB, SW4 VGA, etc.