When an exterior repaint fails early in Orange County or the Inland Empire, the homeowner usually blames the paint. In our experience it is almost never the product. Modern acrylics are good. What fails is the bond between the new coat and whatever was underneath it, and that bond is decided in the week before anyone opens a bucket.
Start with washing. Old stucco that has been in the sun for a decade develops a chalky surface: a fine powder of degraded binder and pigment that rubs off on your hand. Paint sticks beautifully to that powder, and the powder sticks to almost nothing. A year later the new coat peels away in sheets, carrying the chalk with it. A proper pressure wash removes it. Skipping the wash is the single most common reason a repaint fails, and it is also the easiest line item to leave off a bid to come in cheaper.
Second is crack repair. Stucco hairline cracking is normal in California, but an unfilled crack is a direct path for water into the paper and lath behind the wall. Those cracks get patched and the control joints and penetrations get caulked before any coating goes on, not after.
Third is priming bare substrate. Anywhere you have exposed stucco, bare wood, or a glossy old enamel, the new coat needs a primer formulated for that surface. Spot priming takes hours. Repainting a failed elevation takes days.
Fourth is film build. On stucco, paint sprayed on and left alone bridges the texture instead of filling it, so the actual dry film thickness ends up well under spec in the low spots. Back-rolling right behind the sprayer pushes the material into the texture. It is slower, and it is the difference between a coating rated for a decade and one that starts chalking in four years.
When you compare bids, look for those four things written as separate lines. If one estimate is meaningfully cheaper and does not mention washing, patching, caulking, or priming, you are not comparing the same job. You are comparing a paint job to a coat of paint.