There are tons of opportunities on Craigslist if you keep your eyes peeled, consistently lurking the Craigslist forums. There are possibly limitless ways to make money from Craigslist, but I am only sharing the methods that I know will work one hundred percent for anyone willing to put forth the effort.
Offering a Service
This is the best way I've found to make consistent money, post adds to do odd jobs, whatever might be needed in your town from hay hauling to moving jobs to dog-walking. It doesn't matter if you are a professional or not as long as you post a professional looking add, if you post one add every hour, you should get enough work to quit your day job.
Reconditioning Free Items
Often times you can get a priceless gem such as a flat screen or projectors for free that just need a little sprucing up, a coat of paint, stain or polish to make the item worth a hundred times its value, then resell it on Craigslist.
Buy Low, Sell High
This is a very easy method to make money on Craigslist, it requires some starting money, if you know what you are doing you will always come out on top. The hottest items for this is electronics, specifically smart phones, it's easy to find or ask for a good deal, do not be afraid to low-ball people, then sell it at average acceptable price for a nice profit.
Repair Broken Electronics
There's always someone with a broken iPhone or Xbox 360 or PS3 or flat screen that just needs one minor $15 part replaced to make it work again and all you have to do is put in the effort, time, and money to google the knowledge you will need to repair it and order the part.
You can either repair it for them at a cost or buy the electronic at a 1/5th of its value and fix it for yourself and then resell it.
Amazon Price: $25.00 $13.94 Buy Now
(price as of Mar 19, 2014)
Find Work & Sell Jobs
Often you will meet an out of work electrician or arborist or someone with special skills, offer to help them out and get them a little work, in exchange he has to give you a part of what he works for every day. Post adds for them until you get them work then charge a quarter of whatever they worked for in the promise of another job tomorrow.
This is by no means a definite way to make money, but i can guarantee you that the more time & effort put into Craigslist the more Craigslist will reward you, this is not meant to be a complete list of the ways to make money on Craigslist either.