Why a fixed weekly schedule fails here
A fixed schedule assumes a steady rate of soiling, which is exactly what an irregularly used building does not have. Attendances land on empty weeks and miss busy ones, so the facility is simultaneously overpaying and under-serviced. The usual response is to add frequency, which increases the cost without solving the timing, because the problem is not how often but when relative to actual use.
The better structure separates the two needs. A base attendance keeps the building maintained regardless of use, covering amenities, dust, entry areas and anything that deteriorates with time alone. Called attendances handle actual events, sized to what the booking involved. Comparing providers on how well they can offer both is more useful than comparing them on a weekly figure neither structure really fits and it is a structure most providers can quote if asked.
