I built this website to crawl PTT Gamesale (PTT is like Reddit in Taiwan) every three hours, extract game data from posts, and present them in a searchable and filterable table. When selecting a specific game, the price trend will be visualized.
It does exist other similar websites. However, they can only extract data from a single game (there are often multiple games sold in a post) due to the unrestricted formats of the post. On our website, we use OpenAI GPT-3.5 Turbo API to extract game data (about $2 per month), which can extract multiple games and other properties, such as whether the items are new or used. Then, we employ Fuzzy Search to find the closest game from the game database I organized to solve the problem of different names of the same game.
This website is currently an MVP. There are many spaces for improvement, such as improving the game database to increase accuracy, subscribing to the price notification of a specific game, etc.