I just bought a rental property in Huntington Beach, California. The fiberglass shower base has several cracks near the drain and I can feel the soft spot around the cracks. I was told the cracks were there for more than 3 years. Please advise how they can be repaired. Is a base liner necessary to place on top of the old base? Where can I purchase the liner? Is there any repair services you will recommend in my area? What will be the estimated cost? I would appreciate any suggestions you would give me. Thank you.