I have a driver/beater that I have to sell and it bothers me a lot to have to pay for an ad on Craigslist that was formerly free. The way I see it, you pay $5.00 for a 30 day ad that is 6 pages back in a couple of days. It will have practically no exposure at that point. If they want to charge for ads, there should be a 'refresh' button so you can go to your ad and 'top post' it every few days.
On a related topic, where is a good place to post a free car for sale ad besides Auto Round Up and Facebook Marketplace?