The most expensive portable restroom type you can rent is a restroom trailer. It is a towable unit that provides a permanent bathroom experience with multiple stalls, flushing toilets, vanity sinks with running water, mirrors, interior lighting, and often climate control. The cost is driven by the unit's complexity, amenities, and the need for power and level ground setup. A restroom trailer requires a generator or shore power connection, a fresh water tank or water hookup, and must be leveled upon placement. Its waste is stored in a large holding tank serviced by a vacuum truck, just like a standard portable toilet. For your event with 200 guests over six hours with alcohol and food, the industry guideline suggests more units than a basic calculation of one per 50-75 people due to the duration and alcohol. You would likely need a multi-stall trailer or a cluster of high-end units. Service frequency for an event this length is typically handled by a pre-event setup and post-event pickup, but heavy use may require a mid-event service. The setup differs from a standard cluster by providing an enclosed, climate-controlled space that reduces lines and elevates the guest experience. Always include an ADA-compliant unit if you cluster any portable toilets on site, as the ADA Standards require at least one accessible unit per cluster where multiple units are provided.