Free classifieds are a place you don't want to go. They are a wasteland of resellers hoping to sell something to each other. Most reputable businesses don't even bother and why would they? Their customers are not going to be searching the free classifieds for products or opportunities.
It just makes sense that the value of a free ad is zero. While the concept is hugely beneficial to the owner of the classifieds who gets a huge volume of potential clients and conversions while capturing your data in the process, it has no value to you. You will not make money here.
If you don't have any money for advertising, I would suggest a part time job to jump start your effort. There are many places where for a small fee you can place an ad that will get respect from the readership. You are, by the way, looking for credibility.
Again, don't waste your time. I don't recommend free classifieds.
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