How much did your Phantom cost you again?
I estimate that have spent around $150 on parts alone for my Phantom DIY keyboard. $50 for Phantom plate and PCB, ~$50 for switches, ~$20 for controller, diodes and stuff. Keycaps, stabilisers and parts I built the case of were scavenged from several cheap vintage keyboards. The cable is from a broken camera.
That sum does not include the cost of shipping of the parts, the tools, solder, wick (or my time), but I have also other custom keyboard projects that I had bought parts for at the same time...
It also took me a bit of hunting, scavenging and WTB threads on the forums to gain these parts during several months.