1) The npc_price function was added to let you know if an item can be purchased from an npc currently, and if so, at which price. If npc_price is greater than 0, then mafia knows that the market is unlocked. If npc_price is 0, then it believes that it's not available yet, and that's why BCA is failing. If npc_price is greater than 0, and you have enough meat for whatever it is, and buy forged identification documents gets them for you, then something is definitely wrong with BCA.
2) Basically the start was just that current latest mafia doesn't strip it for me because mafia knows that it belongs. When familiars are new, mafia's maximizer will strip them of their gear. After mafia knows they go together, it shouldn't. Basically, when it's stripping your barrel, equip the spigot manually, switch to the maximizer tab or window, and re-run the most recent maximizer string and look at what it suggest. It should say that it is unequipping the spigot. When it does so, please post the maximizer string and we can sort out why +regen is a bad thing.