Extras Agency

Hi there! I am looking to join an extras agency just to supplement my income doing something strange. I am looking for any information anyone has, pros or cons, in regards to extras agencies. I know there is a thread on here already in regards to this but it is almost four years old and things change pretty quickly. I have acting training but am just looking for extra work at the moment. Anything and everything you can post will be appreciated and probably not just by me. I'll start the ball rolling by saying I once signed up to TalentBank (this is a few years ago now) I paid around $200 for 12 months and a photo session. The photos were terrible and I didn't get a single job. I now know to not sign with an agency that asks for a joining fee. Thanks for your time!