When buying a house, be sure to change the locks immediately. There is no telling how many people had access to the previous owner's keys. When renting, be sure to ask about the landlord's key-control policies.
Install a low-flow shower head with a maximum flow rate of 2.5 gallons per minute or less. You’ll cut your bathroom water use by 30 to 50 percent, and you’ll conserve the energy required to heat the “extra” water.