If your bathtub/shower or sink drain clogs, you may be able to use a drain cleaning tool to fish anything stuck in the pipe out. You can normally find these tools in hardware stores. Using a hair catcher can also prevent future clogs. Don't use chemical products to clean your pipes or you could damage the system.
If you lose electrical power in your rental property, call your utility company first. There may be localized problems on the grid or there could be a problem with your account.
Tripped Circuit Breaker
If you overload the electrical circuit and trip your breaker, your power will cut. Locate your beaker and check that the lever is in the "ON" position. If it's not, flip it back to that position to restore power access. If a GFI outlet is not working, try to press the reset button to see if that resolves your issue.
If your air conditioning or heating isn't working properly, check the settings on your rental's central thermostat. It's surprisingly easy to accidentally change the settings, which will cause problems with the system. You may have to change the battery on your thermostat to correct the issue.