I agree with Art that RemoteRig is the best solution for remote K3 operation with a K3/0 mini. It works extremely well and seamlessly over hundreds of miles to a remote and isolated radio site. How do I turn on the K3 remotely? Just tap the power but on the K3/0 and RR takes care of it. Every front panel control does exactly what it would do locally. I operate remotely 80% of the time and no one can tell unless I say so. SSB, CW, data, no matter. I can use dual receivers in stereo mode no problem.
I too tried VNC Remote Desktop control of a radio site PC at first but it was slow, unreliable and used far too much expensive data for my limited internet plan. RemoteRig is far far more data efficient.
In my case, the initial set up was complicated because my remote internet connection is vvia wireless cellular modem and the service provider uses private IP addresses that do not access incoming connection requests. Almost everyone told me about that RemoteRig could not work in this situation but I found a way using a VPN. It’s been rock-solid for many years.
No regrets on RemoteRig from me.