My Family's Pawnshop Connects Past and Present

The protagonist is an unemployed young man who can’t find work. With no other choice, he first inherits the small pawnshop his grandfather left behind, which is on the verge of closing. To his surprise, the shop hides a secret portal through time that only he can enter. Whenever he goes through it holding an object, he arrives in the era when that object was made. Thus begins his fantastical journey as he transmigrates between past and present.