If your browsing Craigslist, a Schwinn Jaguar is a sturdy bike. It's multi speed, but the whole rear gear assembly unscrews, and you can screw on a single speed freewheel. It has linier side pull brakes, which will stop you nicely. A single speed Beach cruiser will have coaster brakes...not good, unless you find an older model (made in the USA). Now they are mostly on lost cost bikes. All I use are sidepull and I prefer them over disc. (unless you find a $100 bike with hydraulic disc...snatch it up.