Pre-war apartments, long tenancies, and salt in the air.

A unit that's been lived in for twenty or thirty years has a tub that's been cleaned twenty or thirty years' worth. The enamel is worn thin rather than damaged — no big chips, just a surface that has gone porous and gray and won't come clean anymore. That's the ideal candidate for refinishing, because there's very little to repair and a lot to gain.

The pre-war apartment buildings north of Wilshire and in Ocean Park often still have their original cast iron tubs and their original tile. Replacing either means opening a wall in a building where opening a wall is complicated. Refinishing doesn't.

Being three blocks from the water also matters: salt air is hard on chrome and hard on grout, and bathrooms this close to the beach tend to have ventilation problems that show up as mold in the grout lines. Worth mentioning when you call, because mold fed by a real leak is a repair before it's a finish.