"LetsPostIt" is not a major player like Craigslist or Facebook Marketplace. Instead, it belongs to the graveyard of generic classified ad websites launched between 2010 and 2018. These sites are often "template clones"—simple PHP scripts allowing users to post items without registration.
Note to the user: If this keyword was provided to you as a riddle or a data entry error, please clarify the context (e.g., "I need a product description for a car wash special on July 25th") for a revised, safe, and commercial article. LetsPostIt - Shrooms Q - Mobile Car Wash -25.07...
Sites like LetsPostIt are SEO goldmines for long-tail keyword aggregation. Because they have low domain authority, they rely on specific, bizarre strings to rank. A user searching for "LetsPostIt" is likely looking for: "LetsPostIt" is not a major player like Craigslist