I'm in the neighborhood of 130,000 miles in the last 20 or so years. I've broken a lot of stuff, but less in the last few years as I've lost weight and got old. 4 frames, 3 pedals snapped, countless spokes and wheels, saddles, seatposts, a stem, cables, chains, etc.
I've also been a car mechanic for 35+ years and I can tell you no matter how you prepare, stuff will happen. Be ready to deal with it and you will be fine most of the time. I've rarely sagged and I don't own a cell phone. A lot of my routes have no cell service, anyway.