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 for a good time. A trip to the sender's address proves deadly serious when the police and Soo-hyun find a man's dead body.
Unfortunately the movie Don't Buy the Seller is not yet available on HBO Max.
| Directing | Park Hee-kon | Director |
| Costume & Make-Up | Kim Jung-won | Costume Design |
| Editing | Han Eon-jae | Editor |
| Sound | Jang Young-gyu | Original Music Composer |
| Art | Kim Soon-geun | Props |
| Art | Lee Mi-kyoung | Production Design |
| Sound | Ahn Sung-il | Production Sound Mixer |
| Visual Effects | Hong Jang-pyo | Special Effects Supervisor |
| Art | Nam Seong-ju | Set Decoration |
| Crew | Kim Jung-min | Martial Arts Choreographer |
| Editing | Han Young-gyu | Editor |
| Writing | Park Hee-kon | Writer |
| Camera | Baek Yoon-seuk | Director of Photography |
| Production | Kim Kwan-hun | Producer |
| Production | Hong Jeong-in | Executive Producer |
| Lighting | Lee Chol-o | Lighting Director |
| Sound | Lee Ki-jun | Sound Supervisor |
| Production | Cho Byeong-yeon | Executive Producer |
| Visual Effects | Kim Byeong-rae | VFX Supervisor |
| Costume & Make-Up | Park Song-hee | Makeup & Hair |
| Editing | Park Jin-young | Digital Intermediate |
| Camera | Hong Eue-su | Key Grip |
| Writing | Kim Dong-hoo | Writer |
| Editing | 이정민 | Digital Intermediate |
