Penny Pinchers (2011) on Netflix

Plot summary

Chun Ji-woong has a college degree and no job. He fails interviews and lives on money his mother sends from the small restaurant she runs in the countryside. When she stops sending it, he cannot pay the rent on his small apartment and faces eviction. Gu Hong-sil, who lives across the hall, is extremely frugal: she collects and sells recyclables, searches abandoned homes, takes sugar from coffee shops and walks anywhere within ten kilometers to avoid bus fare. She considers dating a waste of money. Because her savings plans require a bank account in someone else's name, she offers Ji-woong a bargain: follow her instructions for two months and share in a short-term moneymaking scheme.