So what happens when an agent finally offers to represent you?
You should carefully research anyone you submit to before ever sending your work to them. Check their website, if they don't have one, be suspicious. That doesn't mean their iligit, it just means you'll have to work harder to find out about them. Check their client list then research their clients. If you can get a hold of some of their clients and talk to them, even better! Make sure you have good solid contact information for the agent. Ask your writer friends in the biz if they've heard of this person, or ask on forums like AN. Check http://www.writerbeware.com/
An agent should never ask for money. NEVER. Period. A ligitimate agent gets paid once you get paid, not before. An agent shouldn't recommend a copy-editor. They may recommend that you have your manuscript copy-edited, but if they try to give you the name of someone then that probably means they are getting a commision and that the agent may not be entirely legit. Most legit agents will absolutely not charge a reading fee either. The only thing that should cost you is sending your query or manuscript to them (postal charges, ect.)
Once an agent offers to represent you, be ready to work hard! Most will recommend changes and expect them to be done before they begin trying to sell your manuscript. Then get ready, because the wait starts all over again while they submit your work to publishers!!
As always, best of luck!