I'm interested in buying a used bicycle but don't really know what is or isn't good. I'm trying to get fit so I'd like to bike to ride around my neighborhood which is flat, for the most part. I've found some bicycles on craigslist but again, I don't know what to look for other than a bicycle with gears. I'm 5'2" so a big bike probably won't be too good for me... Will these bicycles last me awhile and which is the best for the price listed? Here are the links to what I've found.
http://losangeles.craigslist.org/wst/bik/1355659238.html
http://losangeles.craigslist.org/lac/bik/1362970725.html
http://losangeles.craigslist.org/wst/bik/1360604758.html
http://losangeles.craigslist.org/wst/bik/1358998295.html
http://losangeles.craigslist.org/lgb/bik/1361247329.html
http://losangeles.craigslist.org/lac/bik/1358489223.html
http://losangeles.craigslist.org/wst/bik/1355659238.html
http://losangeles.craigslist.org/lac/bik/1362970725.html
http://losangeles.craigslist.org/wst/bik/1360604758.html
http://losangeles.craigslist.org/wst/bik/1358998295.html
http://losangeles.craigslist.org/lgb/bik/1361247329.html
http://losangeles.craigslist.org/lac/bik/1358489223.html