Find it exactly, then open the floor once.
The water bill doesn't lie, but it's usually the only one talking. A hidden leak in a La Mesa house, and the older hillside homes have plenty of original pipe to spring one, announces itself sideways. A bill that's climbed two months running. A warm patch on the floor with no explanation. Water pressure that's quietly slipped. A meter that spins with every faucet off. None of it looks like an emergency, which is exactly how hidden leaks buy their time.
The mistake people make next is understandable. They wait, hoping it resolves, or they let somebody start opening walls on educated guesses. There's a better order of operations. Modern detection equipment finds leaks without destruction, listening through the slab, reading temperatures through walls, tracing lines under floors, and the search ends with an exact mark on the exact spot. Then, and only then, does anyone talk about opening anything, and the opening is surgical instead of exploratory.
Every so often the search finds nothing at all, and truthfully, customers who get that news walk away relieved. The fear is off the list, the mystery moves to something smaller, and the house stops feeling like it's hiding something. That relief is a real service too. Whichever way it goes, you'll know instead of wonder, and the decision about what happens next stays entirely yours.
"My bill doubled and I couldn't find why. They pinpointed the slab leak in one visit and opened the floor exactly once."