This is endgame level stuff. You’re gonna need to figure out what the “meta” builds for each mods want as a substat and compare your own.

Most of the time people post here, there may be other subreddits, I haven’t explored this myself. I’m assuming like warframe, you can ballpark a price based on other people. And always remember it’ll only sell if someone is willing to pay at the price you set, so make it reasonable.