Add an ncp next to the pcs/nursejoy and have the option to sell ur pokemon to him money you get would based on ivs/race/nature. Also, every {X} amount of uses, he charges a service fee of {Y}. for example, u sell 5 magikarp and then he charges u 100k or something.
This is to making cleaning out trash profitable, but the trash has to be mildly valuable or u will lose money.
For example. I sell 20 4x31s, get 50k for each, service charges 100k every 5 pokes, so Profit
Otherwise. I sell 20 random shits I caught with pokeballs, get like 3k each, and lose a lot of cash