Freelancer.com has too many job posting fees not baked into the freelancer bid amount. I also found it to be the worst user interface out of all the freelancing websites I've used. It's very unintuitive and difficult to navigate between proposals and candidate profiles. I was too turned off by the poor UI to hire anyone after receiving bids.
Note: I used to have a separate review of Scriptlance, but they have been acquired by Freelancer.com and are no longer a separate site. My experience with Scriptlance was very poor as well so it’s fitting they are together now.