"Be careful, you might step on a rat or something."
I warned Stanley, but he looked over his shoulder and chuckled at me. He stepped into the thick liquid without another thought. The smell alone in the sewers had been enough to make me gag at the beginning of our little escapade, but seeing my mentor so nonchalantly hopping into the filth made me honestly second-guess my sanity.
"Why would I? A ratcatcher has just been here. The sewage is as safe as it gets."
Not much have changed from those times. The rats and other critters are still sometimes a menace, especially in settlements that are 'off the grid' or not known by the common folk. Underground settlements, 'Shadow Cities' as they are often collectively called, are especially vulnerable as they are often connected through tunnel systems and interlink with ordinary sewers. And the sewers are the domain of rats.
Usually the ratcatchers are either nimble individuals or urban druids, depending on the approach on the profession. Those nimble enough to catch the rats often just kill them or throw them in a sack to relocate them elsewhere, but the druidic persons persuade the animals to leave. More often than not the gentler approach has longer lasting effect on the local rat and mice populations.
Payment & Reimbursement
The pay depends completely on the gig one can get. If you get hired by a governor or mayor of some shadow city, the pay could actually be quite good, but the poorer people who suffer the most of the presence of rats (otherwise they could probably afford to live elsewhere), often doesn't have much to offer for a payment to a ratcatcher.