Bosco's business style appears to be based around overcharging for any item so he can afford his elaborate high-tech, homemade security systems, as well as selling his personal brand of "BoscoTech equipment", which are generally rudimentary at best, but cost extraordinary amounts of money (like a hundred million dollars for a "Truth Serum" - which turns out to be a bottle of Vodka). Throughout Season One, his paranoia causes him to dress up as different people (such as an English man, a French man, a Russian man, and even his own mother). These disguises usually involve nothing more than Bosco wearing a hat or make-up. He still wears his ordinary clothes, and even his name tag saying his name.
At some point between Seasons One and Two, Bosco uses the money he made selling his BoscoTech items to Sam & Max to equip his store with even better security measures and various detection apparatus. He also covers the windows in aluminum foil, dims the lighting to a red glow and stops selling things. This is mostly because of his newfound fear of being abducted by T.H.E.M., which turns out to be justified as they do abduct him sometime between Moai Better Blues and the end of Night of the Raving Dead. He is found relatively easily, but it takes Sam & Max Chariots of the Dogs and a significant part of What's new, Beelzebub? to completely save him.
Bosco has a peculiar relationship with his mother, Ms Bosco. In Chariots of the Dogs, Bosco inadvertently travels back through time and causes a mess in her store. While Sam & Max manage to repair most of the changes to history this causes (including Bosco being a cow), this nonetheless makes her seek revenge and enlist Flint Paper to try to track him down, unaware that he is actually her own future son. The truth about all of this only comes out after she dies in What's new, Beelzebub?. At the time she also mentions how she sent Bosco an alarm clock every Christmas, which he always took to be a bomb and promptly disposed of.
One of the first test-tube babies, Bosco was "born" in a machine, rather than his mother's womb. It is implied that his father is John F. Kennedy, which may explain his paranoia and obsession with conspiracy theory.
In the time before Sam & Max Season Three, Bosco has travelled with Bluster Blaster to Las Vegas. In the first episode of the season, Sam & Max found a letter from him sent to Ms Bosco, telling that he needs 20.000 dollars to resolve his problems with the casino owners. In episode four, Sam & Max find Bluster Blaster in the harbour, saying that he doesn't want to deal with a person like Bosco ever again.