To get some coin flowing, Mina will offer her acid to the living people of the citadel - not as a specific job, but as a "use it for whatever". It can be used to melt things, to get rid of garbage, to even clean stuff at a low acidity. Would this be easy for Mina to do (given that she hides her skin, etc etc), or would people be a bit too weirded out by some chick with acid?