I Support My Wife by Collecting Scrap

Song Lansheng is transported to an ancient world in the middle of nowhere. A System tells him he's been linked to a modern recycling station, where he can exchange scrap goods for items of equivalent value. Used clothes are bought for twenty cents per jin, but sell for one hundred wen apiece in the ancient world. That's a thousandfold profit. Finance whiz Song Lansheng: There's potential here. Covered in dirt after spending half a day digging up mushrooms, Song Lansheng wants to trade for fifty jin of used clothes to sell to the locals. He plans to grow this little business into a global enterprise. He contacts the recycling station owner, who replies nonchalantly, "Some new kind of scam?" Song Lansheng jumps up in outrage. "I'm the one who got scammed by the System!" System: It's real! The owner's Jiang Ce. You two know each other! Song Lansheng has no idea why Jiang Ce, once the talk of their high school, has ended up tending a run-down recycling station, all listless and unmotivated. Still, with a workaholic like him around, Jiang Ce is out of luck. "Your recycling station is full of cardboard. Start collecting used clothes instead. They're the easiest to sell." "Drink bottles, glass jars, sweet potato vines..." "And get me a junk bike. Fix it up for me." "Big brother (*/ω\*) come on, please?" Jiang Ce: "..." What can he do about his first love? He even gets up in the middle of the night to ride his tricycle through every street and alley collecting scrap. Later, the trading system keeps upgrading. Discarded love letters (?), illegal buildings, cement roads, old-town redevelopment... In a country busy with major infrastructure projects, there are just too many things to buy! Song Lansheng becomes a great lord in another world and builds up some assets. He asks the System, "How many mountains of gold would it take to buy that good-for-nothing, too?" System: What good-for-nothing? President Jiang has also become a billionaire from selling scrap! Song Lansheng fumes with embarrassment. "So, are you selling him or not? I can pay plenty, too." Jiang Ce: "I'm selling." Welcome to my city-state. A slice-of-life story about buying and selling scrap. Everyone's welcome to sell scrap to the protagonist. Theme: Turning waste into treasure