> San Francisco has an attended 24 hour portable restroom operation in poor parts of the city, called "Pit Stop". Total operating costs are around $30 per flush

> San Francisco has an attended 24 hour portable restroom operation in poor parts of the city, called "Pit Stop". Total operating costs are around $30 per flush.[2] This is some questionable math. They took the costs of the units and staff and divided by the number of late night usages to arrive at ~$30 per usage. But if they were used twice as much that rate would be halved, etc. In any case the fixed costs are the same regardless of usage metrics. It's very misleading to take a highly fixed cost and label it like a usage-based cost.