In 1984, PolyJohn engineered the next big advancement in portable toilets when they built the first luxury restroom trailer. This trailer was a whopping 32 feet long, had eight stalls, and offered a new level of luxury and odor resistance that had never been seen before. Today, portable restrooms are further refined to the exact use you need them for. Construction restrooms are on trailers, allowing them to be easily moved to follow crews building roads. Hook restrooms have a hook installed in the roof so a crane can lift them to the upper levels of buildings. Skyscrapers even have their own form of portable restrooms, which can be folded down and fit into a construction elevator.