This method involves a little bit more work, but not much. Many businesses could beneﬁt GREATLY from having Craigslist ads posted for them once a week or once a day even.
Craigslist gets over 10 million visitors a day! This can obviously be a great selling point for this service. Once a business owner hears that and conﬁrm it (if they need to), you will be able to charge them for this service with no problem.
You can package together different options, such as "5 Craigslist Ads Per Week for $XX" or "One month of Craigslist advertising
I think $10 per ad is fair for offline businesses (considering they pay the Yellow Pages and other advertising companies MUCH more money!). If you do 5 a week for them, that's $50 a week which comes out to $200 per month, from just one client. It should only take about 5 minutes or so to post a Craigslist ad for someone, it is not difficult at all.