Don't trust recruiters. They work for the employers not for you and their best interests are served by getting you a job quickly and satisfying their real clients rather than getting you the best job they can.
I would simply say that £x is the minimum you're willing to accept and be comfortable in the knowledge that if you can get one job offer like this you can get another.
No, IME recruiters do not act remotely on the employers side, their default t&cs usually have inverse tiered rates, e.g. 15% of first year salary upto £40k, then 20% between 40 and 50, with 25% from 60 upwards, that is based on 20 agencies I've dealt with. They will deliberately pitch the candidates at their highest tier despite it being over industry standards. Since we insist on largely dealing with candidates directly, we've found they screw over both sides, we've turned average people down purely on inflated expectations that came from the recruiters, the candidate was asking for much less, and when we found out, and aproached them directly, we offered them a fair salary, and of the 4 offers they had, we where still the highest, despite being £5k under the recruiters stated expectation.
It possibly depends on the sector, but engineering and IT most certainly work like this.
It's funny to see both sides of agencies, they are ridiculously off the wall and act against both parties best interests, their greed and dodgy tactics is almost second to none from first hand experience and catching them out. there are one or two good ones, and its no surprise that we tend to stick with those that act fairly and above board, but when you are trying to recruit and there are less candidates than jobs, you really do need to suffer the pain of managing agencies.
In the OP's situation, it's tough, it sounds like standard Agency practices of building false expectations probably on both sides. I could be wrong, and often am, but from direct experience, this is how I've had about 10 candidates pitched to me in the last year.
- Recruiter told candidate they could get £10K over their current salary which they said was low for the industry.
- Recruiter obviously knows the employers salary range but still puts the candidate forward to the employer with high salary expectation, employer says no, but recruiter tries to say how special they are etc, and definitely worth interviewing.
- (I stop at this point normally after I'd been stung twice)
- Interview occurs, candidate is good, but in the 'normal' range
- Employer realises that whilst the candidate is not worth the £10K over their salary band, they are worth a fair market offer
- Recruiter now has to go back to candidate with what seems a low ball offer
Of course, some companies don't move with the times, and have built up a department of people who are below market value, and their expectations can be out, but thats all part of it, look around and see what salaries are being advertised, take off approx 5-10% of the advertised value and that is usually around the actual going minimum rate.
/rant