Yeah, take a magnet shopping. I'm assuming that you are looking at front hubs and want some kind of primitive suspension. In Wally world the other day, I was looking at a bike with slightly better front forks but still steel. It was a Mongoose, selling for just under $200 localy, which had front disk and rear rim brakes. No posts on the forks for rim brakes though, so that may be a deal breaker. My solution has been the next bike down the price list, which comes with front and rear rim brakes, and front forks that have the dropout formed by squashing the steel tube. The suspension is super lame, about 40 mm, and very prone to bottoming out on any chuckholes. But it does feel better to me than regular steel forks, and helps me to have less problems with hand fatigue on really long rides. Under 5 miles, I wouldn't need suspension at all, but for 30 miles a day at my age, I NEED suspension even if it's the cheeze kind. These lower level bikes come with tinfoil front gears, so you will need to start looking for a good crank immediately at the garage sales. Forget standing the seat for any length of time too, so add $50 to the price for all that right off the get go.
For any front hub, the main thing is to avoid any bike with a quick release front hub, which are notorious for poor fit of the oversize washers and then spinout ruining motors, controllers, and god forbid, teeth.
Going up the price list, my local bike shop has an entry level Trek mtb,( maybe the 820?) with hardtail and a slightly better but still steel front fork. That one retails locally for about $350. For those wanting to buy a bike that doesn't require you to tune it, the extra $150-200 is well worth it. Anything from wally world or a garage sale, craigs list, etc is garanteed to need a real bike mechanic to spend some time on it. So if you aren't one, you'll spend a lot getting it done, or get to learn how. The cheap bikes can run amazing distances when properly tuned, and the really expensive bikes can wear out in just a few miles if left out of whack.
