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.
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 Chul-oh | 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 |
