Forcing your hand means forcing you to do violence upon them. It's about going agro, right? "Force your hand and suck it up" means you've got your gun against their forehead, and they yell "go ahead!" or just stand there and you shoot them. Blam. Inflict damage as established.
I feel really stupid but do you care to elaborate this a bit more, what is the actual difference of yelling "go ahead" and just getting shot? How about the "Direct-brain whisper projection" in the Moves Snowballing example? It counts as going aggro but without going aggro, is "Forcing hand" the same as "You know, fuck you I'm not going to tell you shit, just fucking shoot me already you pussy!" aka not doing what the one going aggro wants. How does this works when someone is just threatening someone?
Barter is just, sometimes as a MC it's your time to talk, and you pick a move, and it's "make them pay for it" and you decide barter is the price. 1-barter, 2-barter sometimes, sometimes more. If they have it, they spend it and it's gone, but they got what they want. Like they're in a shop, and they ask you "so, any gun in there ?" and it's your turn to talk, so you pick "make them pay" and misdirect : "yeah, there's a bunch of automatics behind a chained door. You're looking at them, and a guy pops up and say "like what you see? It's one barter apiece.""
Basically, it's just money, but in large chunk, no pennies.
Sometimes the game itself tells you how much it costs (like 1-barter gets you 2-stock for your angel's kit), sometimes it tells you how much some character get (like moonlighting or wealth).
1-barter is enough to get basic shelter and food for a month. More on barter bottom of p. 101 and full pp. 236-238.
What if the characters can't pay? And must they pay if you choose "make them pay" or could they just walk away? Or does that move just mean, you wont get that for free this time, can this be either Barter or exchange in a favor?
Thank you so much for answering!