Soo-hyun, who has recently moved into a new house, buys a used washing machine through a second-hand app but finds out it doesn't work. Annoyed by the seller's irresponsibility, she leaves a comment calling the seller a con man, and reports it to the police. Little does she know that the seller is a psychopathic serial killer who uses an online second-hand market to lure his victims. Her comment renders his hunt for a new victim all but impossible so she becomes his next target. She starts receiving obscene phone calls, countless unwanted food deliveries, and strange men knocking on her door looking fora good time. A trip to the sender's address proves deadly serious when the police and Soo-hyun find a man's dead body.
Is Don't Buy the Seller on Netflix? Yes! The movie Don't Buy the Seller is now on Netflix in the countries listed below.
| Directing | Park Hee-kon | Director |
| Lighting | Lee Chul-oh | Lighting Director |
| Visual Effects | Hong Jang-pyo | Special Effects Supervisor |
| Costume & Make-Up | Kim Jung-won | Costume Design |
| Crew | Kim Jung-min | Martial Arts Choreographer |
| Sound | Ahn Sung-il | Production Sound Mixer |
| Art | Nam Seong-ju | Set Decoration |
| Art | Lee Mi-kyoung | Production Design |
| Editing | Han Eon-jae | Editor |
| Art | Kim Soon-geun | Props |
| Sound | Jang Young-gyu | Original Music Composer |
| Production | Hong Jeong-in | Executive Producer |
| Editing | Han Young-gyu | Editor |
| Writing | Park Hee-kon | Writer |
| Camera | Baek Yoon-seuk | Director of Photography |
| Production | Kim Kwan-hun | Producer |
| Writing | Kim Dong-hoo | Writer |
| Camera | Hong Eue-su | Key Grip |
| Visual Effects | Kim Byeong-rae | VFX Supervisor |
| Sound | Lee Ki-jun | Sound Supervisor |
| Costume & Make-Up | Park Song-hee | Makeup & Hair |
| Production | Cho Byeong-yeon | Executive Producer |
| Editing | Park Jin-young | Digital Intermediate |
| Editing | 이정민 | Digital Intermediate |
