Stan first appear in The Secret of Monkey Island, where he runs a used shipyard on Mêlée Island, which he seems to have been running for quite some time since almost everyone on the island seems to have heard of him. He is portrayed as a stereotypical used car dealer. He talks very fast and pelt his customers with information and enthusiasm about the ships he's selling and never misses a chance to mention that the deal is much better for the buyer than it is for him. Guybrush is able to fool Stan into selling him a ship with a stolen credit note.
This portrayal of the Stan has been around for all the subsequent versions of Monkey Island. He also has a very intense body language with very large and rapid gestures, he impatiently stomps his feet at all times. Stan has a strange sombrero like hat and a long coat that is always checked in the same way, like a grid pattern, which then never follow his movements.
In Monkey Island 2: LeChuck's Revenge Stan becomes nailed inside a coffin by Guybrush Threepwood and is later buried alive in a crypt. He isn't released until The Curse of Monkey Island and has miraculously survived without any physical or psychological harm at all. In fact he thanks Guybrush and says that it was the best time of his life and that he has decided to venture into the life insurance industry. Remarkable is also that he already had the time to print new business cards.
Although he has a tremendous drive and passion for his job he never seems to be particularly successful, he has never had the same job for more than a game and there are many references to earlier firms Stan has had. He has a reputation for being somewhat of an imposter, yet his talent is recognized at times.