The Terpco Sentry Drain Cover brings one man and one product to the work sight. Tarp & sand requires 3 men, a truck and materials. The Terpco Sentry Drain Cover took a total of 30 minutes with an average cost of $1000.00 to prepare for this match. Tarp & sand took 27 hours and had a staggering cost of $1560.00. That’s a difference of $560.00 , not including tarp & sands clean-up and disposal fees!