Bicycles can be a great way to save a considerable amount of money in transportation in addition to the obvious health benefits. One way to save money on a good bicycle is to buy a used bike. Many times you can buy a slightly used bike for ½ the price of a new one.
 
Things to look out for when buying a used bicycle-
 
Make sure you buy from a reputable person in a better part of town; you don’t want to end up buying a stolen bike.
 
Look up the model number and frame size on the internet-
Looking up the model number can tell you a lot of valuable information about a bicycle such as how much the bicycle cost brand new so you can tell if you are getting a good deal on a used one. The model number can usually lead you to reviews of that exact bicycle. Spend some time and see what kind of problems other people have had with that model of bicycle before you buy one. Knowing the frame size can tell you if the bicycle is the right size to fit you body and your riding needs.
 
Try to find a bicycles that has been gently used-
A lot of people buy bicycles with good intention and rarely ride them, which is great if you get to buy one. Beware of people who abuse and trash out bikes by heavy use or by lack of care.
Things to look for to judge the amount of use a bicycle has had- looking at the rubber parts on the bicycle tires, brakes and handle grips can tell you a lot about how much use a bike has had. How much wear do the tires have? Are they wore down from a lot of miles or cracked from sitting out all winter? Are the brake pads worn down from a lot of riding? Do the handle grips have a lot of wear from use? If these parts you can see are worn, chances are the internal parts are worn as well.
 
Look for a rusty chain, bare cables and other exposed metal parts. A lot of rust usually indicates that the bike was left out in the weather and not cared for. Too much rust on components means they will not function well and will need to be replaced in the future.
 
The initial investment in your bicycle is usually the biggest expense, but if you plan on using it frequently, it is good to get a good high quality bicycle.
Most of what you pay for in a bike is the metal it is made out of. Lighter bikes are made out of aluminum or lighter weight metal, which is more expensive, than basic steel. Lighter bikes are a lot easier to ride long distances, carry up and down stairs, or load onto your car or the bus if you do a lot of biking.  You also pay more for quality components such as gears and brakes. Good gears can make bike riding much nicer than trying to ride around while shifting clunking, malfunctioning gears.
However, you likely don’t need a top of the line, feather light, titanium, $4000 bicycle just to get around town. If you spend too much you have to worry more about it getting stolen.
 
Time spent researching and reading reviews can be very valuable in finding the right bike for you.