Many states exempt sales tax on utilities for multifamily properties. Check with your Department of Revenue to confirm the exemption. If your property is exempt and your property is currently paying sales tax you may file for the exemption to be effective at the next billing cycle. This could save 5% of your water/sewer expense. You are also able to request a refund on the previous 3-5 years of payments. This can produce thousands of $ for your properties.