New build with recycled parts on a ridiculous budget 120cm*60cm work area

[Neale]

Another opinion...

5 BOB inputs is just enough. I'm assuming you are using microswitches here - it gets a whole lot more messy if you want to use inductive sensors. All limit switches and home switches can be wired in series to one BOB input except the X slave home switch which must have its own input. I would only use one X limit switch, BTW - that should be fine. One input for touch plate. One input for estop and fault signals in series. This is because a motor stall fault needs everything to stop fast before the gantry gets twisted sideways. And there's still one input spare!

If you really wanted, you could take the Y home switch to the spare input. This buys you the ability to simultaneously home X and Y to save a second or two during homing. I've done that on my machine just because it looks neat but it's hardly essential.

I'm afraid I don't know how slave axis homing works with LCNC - I switched to Mach3 from LCNC before slave homing became available.

I would take 5V to the 5V input terminals. The 12-24V input is for a separate PSU and you would need that to use the 0-10V analogue output for VFD speed control. Otherwise the BOB can't generate enough output volts from the 5V supply - common problem with 5V BOBs.