GE Add on switches

I know these things are for 3 /4 way uses but has anyone figured out a way to use existing 3/4 way switches minus 120v only using the traveler line? even at $20 I’m looking at like 20 or more to retrofit my home… and that’s a bit excessive.

soooo… Anyone got ideas?

The add-on switches only serve to tell the main switch what to do. All zwave logic is in the main switch.

This is what I did instead of the expensive add on switches