np.
Ideally, with a little experience behind you, eg. City & Guilds in AutoCAD (2d, 3d wireframe, 3d solids etc) and some actual job time to get really proficient with the software or a particular discipline (3-6 months up to a year) you should be able to charge at least £7-9ph for agency contract work.
My last decent rate doing contract work was about £11-12ph plus expenses.
If you have a specific qualification, say engineering or design speciality, then the minimum should be something in the region of 22k+ but that's scraping the barrel somewhat, if you ask me.
If you're going for agency work, chances are you'll never be anywhere long enough to really get a feel for the job. You'll gain some useful experience, but it won't do much for your career learning prospects, playing catch-up to someone else's irreparably damaged X-ref directory, shoddy drawing office standards, or worse, will be pretty much the norm lol.
If you're a novice, then be prepared to accept whatever you get offered (so long as you can sustain it) to gain a bit of on the job time, then ditch it for something with better pay and prospects.
If you can haz CAD skillz don't be too far tempted by anything less than 15k - though you'll find plenty of firms offering min wage for 'monkey see, monkey do' stuff.
In a nutshell - 12-16k = no skillz and needs the money or the time on the job.
17-20k - haz the skills but not super qualified (like design engineer etc).
20k + = some sort of design/engineering/architectural qualification, add decent experience to that and your probably looking more towards 23-25k, with a full on engineer looking at 30-40k +
That's my rough overview of it.
I still say that the level of remuneration that 'mario' wants for the experience he's requested, is derisory to say the least.