Super Soaker

This iconic toy water gun operates using pressurized air to squirt water at your friends. It was certainly the joy of millions of little kids, especially during the summer break. However, this toy brought too much annoyance to many parents. Despite the contrast, the popularity of this toy generated more than $1 billion in total sales.

Back in the day, you could purchase a Super Soaker for at least $10 to $50. If you happen to have the Monster XL and the Super Soaker 50, then you’re looking at a potential return on investment of at least $600. However, demand for these toys often fluctuates, and you’ll need to sell the right water gun at the perfect time to get a tidy sum.