Agencies cannot charge you, but there are services you have to pay for
We'll say it again. An agency works for the client, not you. Their services might seem free - but for a sizeable percentage, usually 17.5%, it's the employer who calls the shots.
Who pays the piper
Under "normal circumstances" that can mean that you pay nothing and the agency does all the donkey-work of getting you into a job. Put like that, you can understand why an agency won't look at you if you don't look like a paying proposition. Unless they can place you successfully in a job with the client, they get nothing.
Predictably, "normal circumstances" are rare and may not even exist. You may not actually pay for getting into a job, but there are various add-ons that could be charged for making it happen.
The cost of bolt-ons
For example, since it's the client who consults the agency and not you, any consultations you may require - usually in the form of advice - are likely to be chargeable.
An agency is not in the business of giving advice. In fact if you need guidance, you're better off seeking it from professionals at your institute of learning or friends already working in the same occupation.
Watch the hard costs
Expect to pay for other things too - perhaps not for photocopies and phone calls, but certainly for any "panel-beating" to your CV and the preparation of any supporting letters in your name.
So if they're not bending over backwards for you, what is your agency doing? Actually quite a lot of client stuff, and it all impacts on you.
Proving that you're you
Once they're committed to putting you forward as a candidate, there's loads of background checks to be done - for instance, your passport to check your ID (not everybody is who they say they are), references from your previous employers (people lie about that too), and checks on your qualifications (fake degrees cost as little as £5 on the Internet).
All of which strongly underlines the need to make yourself look and feel exceptional. They might make a lot of money, but recruitment consultants work hard for it.
The ace up your sleeve
So take a look at yourself again and think about how you stack up. Remember those Clickatest checks on skills and attitude?
Go get 'em!
If you think about it, your job is on the line - the new one you're going to get. Which means the only limit is "whatever it takes". Everything you do to make filling a client's vacancy smoother and easier can only count in your favour!