One of the biggest questions I receive here at Craigslist25.com is: "Can you recommend a good way to get my ad posted a lot without getting ghosted or flagged?"
Note From Shawn: I am STRICTLY an ad designer and I DO NOT offer any posting services.
While I don't have the BEST answer to this question, I can certainly offer some information that I have learned from speaking to others who post on Craigslist multiple times per day in multiple cities. This information is made up from suggestions I've heard from other Craiglist posters and I can not confirm nor deny the validity of these suggestions.
1) Craigslist posting in multiple cities will get expensive very quickly. Some Craigslist ad posting companies charge $2.00 per post! Craigslist states very clearly that these types of services are against the rules.
2) Posting multiple Craigslist ads will require 1 Craigslist Verified Account for every 2 ads that you want to post every 48 hours. Craigslist doesn't want you to do this - it's against their Terms of Service.
3) You should change your IP address (through a proxy) after each new posting.
4) Your Craigslist ad Design should be dupliacted at least 20 times on your server with different image names.
5) You will need a different phone line for each Craigslist account that you register - these can cost $3 - $5 per phone line.
6) You should dedicate 3 minutes for every Craigslist ad that you post. Take your time and ensure that your ad sticks.
7) If your ad is text only, post a different ad every time with different words.
8) Always try to post in the proper section.
9) Always try to have a contact phone number from the area in which you're posting -or- get a 1-800 number that can handle calls from all areas.
If you have any suggestions you can send them to firstname.lastname@example.org