I have 3 of my computers set up on one something like this one and I use the 4th port for an extra hookup when I am working on someone elses computer. It has been working for several years now and I have just now replaced 2 of the cables. 1monitor, 1 keyboard and 1 mouse with headhones plugged in as well. I love these things and they are really inexpensive.
https://www.amazon.com/TRENDnet-4-Po...s=kvm+switches