Dealt with this exact issue last summer at a coastal rental. Salt air destroyed the sensor contacts in under six months. Had to redo the whole setup with stainless parts, which held up perfectly. Always push for the better materials now, learned that lesson the hard way.
Salt air really does a number on electronics, doesn't it? Learned that the hard way when my cheap outdoor sensors turned into rusty paperweights after one beach season. Had one fail right before a big storm, so I was out there in the rain trying to jury-rig a fix. Now I'm that person who lectures friends about marine-grade stainless like a total nerd. Still mad I didn't listen to the guy at the hardware store who told me to spend the extra five bucks.
Actually, cheap sensors can sometimes surprise you near the coast if you keep up with basic care. @kevin_martin's bad luck sounds rough, but my buddy's budget setup lasted two seasons with just regular wipe-downs (and a cheap silicone spray coating). It's not always about spending more, just being a bit more hands-on with maintenance before problems start.