One of the ways you will earn money during the game is by selling the items you find and receive during the Main Story (primarily after defeating foes). Unlike other gaming Series similar to the Yakuza Series, you cannot sell the items you obtain just anywhere. Instead, there are specific locations in both the cities of Kamurocho and Onomichi where you can sell your goods. Much like the real world, these specified businesses are none other than pawn shops.
In Kamurocho, you will only be able to sell your items to the Ebisu Pawn Shop. This little shop can be found just off of both Pink Street and Nakamichi Street in the Hotel District, down the block that actually goes between said streets (literally just north of Showa Street). After you arrive at the Ebisu Pawn Shop, you will be given the option to either buy or sell items. Simply pick the latter option to cash in on your unwanted items.