Fiverr can be a great place to find traffic providers that are in different niche markets and some that have unique sources of traffic that a larger company may not have the time to focus on, as well as a great place for those selling traffic to make their first sales. They have a review system which helps to weed out bad providers and it is wise to avoid listings with previous mediocre or poor reviews, and there are also a large number of people re-selling traffic bought from a wholesaler on Fiverr, and with that in mind you will want to look for sellers that give a good background to their traffic source and who appear to be the actual owners of the traffic source.