We bought a used riding lawn mower at an auction shortly after we got married (Spring 2002). A Yard Man with a 46″ cutting deck, hydrostatic drive, and a 20-HP Kohler engine. We paid $800, which was about a third of a comparable new one.
Once we got the thing running pretty regularly, it's been good. By no means trouble-free, but good nonetheless. There were a few “interesting” fixes that the previous owner did to keep Big Bird running, like using a shorter drive belt when one of the pulleys broke off, instead of replacing the pulley. It was also a little frustrating at the beginning because it started really hard and cut out at a moment's notice. This went away when we replaced the magnetic ignition module. All told, we've probably put $500-$600 in parts in it over the past five years and spend about 100 hours or so repairing and maintaining it. The latest thing to go on it was one of the blade spindles; we went to CheapMowerParts.com (that's not a joke) and got the replacement for $40 plus shipping — about half of what our local store charged. The engine (a good one, from what I've been told) is still going strong, and that's the expensive part, so the other stuff I can deal with replacing.
Would it have been easier to throw in the towel and get a new one? Absolutely. Would it have cost more to get a new one? Yes, because we haven't poured that much money into fixing this one. Would I know as much about fixing lawn mowers as I do now? I doubt it! I call it an investment in making myself a little more resourceful and handy.
In addition, the October 2005 issue of Consumer Reports has an guide on what to repair and what to replace. Lawn tractors and riding mowers have the longest repair life of the 15 products they listed. They recommend repairing the mower for the first 6 years, and recommend that you consider repairing it for at least two more. This is in contrast to electronic items like televisions, which they recommend replacing after 4 years if it breaks.
So, that's a little consolation that my urge to repair Big Bird was justified!
Sometimes newer is easier but sometimes lemons come in new boxes too!
Different lawns come with different cutting needs. Some lawns will need to be cut more quickly than others and examples of these are huge golf courses and outdoor commercial establishments. Determine how quickly you need your lawn to be mowed so that you can also assess what kind of riding mower to get.