Many things affect the final price. The type of water heater matters. Tank models are common. The size of the unit also plays a part. Bigger homes often need bigger heaters. Labor costs are part of the total. Removing your old unit adds to the job. Sometimes, a permit is needed.
It's smart to plan ahead. Get a few quotes from local pros. Ask what each quote includes. This helps you compare prices fairly. Make sure it covers parts and labor. Also check if old unit removal is in the price.