Bathroom re tiled or a bathtub shower liner?

Dear Highland Parkers, I am tasked with finding a reputable contractor to fix our second floor bathroom.  The shower tiles are starting to fall off  the wall (about 3 tiles and the soap dish tile).  We want to either replace the tiles or use a bathliner. Please, offer any advice, comments, recommendations, experience etc.  The house is roughly 100 years old.  We are also trying to be budget conscience and not just use a temporary fix. Thank you very much for your responses. Susan Randall