To prevent clogs and odors in your garbage disposal after installation or repair, make sure to run cold water while using the disposal, avoid putting fibrous or starchy foods down the disposal, periodically clean the disposal with ice cubes and citrus peels, and avoid pouring grease or oil down the drain.

I would need more information about the issue with your water heater in order to provide an accurate estimate for the repair.

If the water pressure in your shower suddenly drops or fluctuates, it could be a sign that repair is needed. This could be due to a clog in the pipes, a faulty pressure regulator, or a problem with the water supply line. To address this issue effectively, you can try cleaning the showerhead, checking for any leaks in the pipes, or adjusting the pressure regulator if applicable. If these steps do not improve the water pressure, it is recommended to consult a licensed plumber to diagnose and fix the underlying issue.

Some common plumbing maintenance tasks to prevent issues include checking for leaks, clearing clogs, inspecting water heaters, and testing water pressure.

As a licensed plumber, you can determine if gas lines need to be replaced or repaired by looking for signs such as hissing sounds, gas odors, visible corrosion or damage, decreased gas pressure, or frequent gas leaks. It is important to consult with a professional plumber to assess the situation and recommend the appropriate course of action.