The average pool requires about $45 of chemicals a month. Driving to the pool store to get your water tested weekly costs about $20/month according to IRS mileage rates. Taking care of your pool will probably take about 5 hours/month. If you make $20/hour on job, it is costing you $100/ month in time.  The total of these costs is $165/month. That is more than twice the cost of some of our pool service plans!