October 2026 craft fair: 400 attendees, mostly women. Units?

Size it off your peak hour across both days, not the 400 total, and lean toward more seats with no urinals, since a mostly female crowd uses a full stall every visit. I run a fall festival with food vendors and the part people underestimate is the lunch rush. Lines build right after people eat, not evenly through the day.

Give the rental operator your peak attendance, hours open, both days, and the fact that food is served, and have them size it off their units per person chart. Book a Saturday night service visit so Sunday opens with pumped tanks and full paper. Skip that and a good Saturday turns into a rough Sunday morning.

A small restroom trailer is a nice comfort upgrade, but I would not let it replace standard units. A trailer has a fixed number of stalls and lines still form. Pair it with a row of standard units and put handwash stations near the food vendors.

Every cluster also needs an accessible unit. The 2010 ADA Standards require 5% of the portable units in each cluster to be accessible, and never fewer than one. Since the truck can drive right up, have them set everything on the flattest part of the field.