Use one timetable for the different suppliers
Share delivery windows, setup, opening and clearance with the rental contact. Explain which entrance is approved and who will receive the facilities. A calendar date alone does not tell a supplier when the site can actually accept equipment.
Prepare for the return visit before opening
Keep the collection route out of storage and confirm the person responsible after guests leave. Discuss service for multiple sessions or extended use. If the programme changes, ask for confirmation of revised visits instead of relying on the original timetable.
A shared layout and a complete timetable
Map the event in time as well as space. A single session, repeated sessions and several simultaneous activity areas can create different patterns of use even when the total attendance is similar. Give the supplier the pattern you expect and identify which attendance figures remain estimates.
Use one agreed layout for organisers and suppliers. Show the toilet group, washing, accessible approach and the route that must remain available for service or collection. Place responsibilities alongside the drawing: who approves a move, who reports a problem and who remains after cleanup.
Give the final site plan a clear version or date. When another supplier changes the layout, review the restroom position and access on that same version to avoid conflicting instructions.