Sorry to her of the issue.
If the agency or the landlord misled you, you can ask them to unwind it - under the Consumer Protection from Unfair Trading Regulations 2008, as you have already mentioned.
This will require the landlord's consent - if they agree, the tenancy should be unwound and if you are within 30 days of living there, you should be given a full refund.
If you have been there for more than a month but less than 90 days, you can expect a partial refund taking in to account the benefit you have from living in the landlord's property. The issue will be if the landlord refuses to unwind the tenancy - if that happens then you are stuck though you can apply to the local County Court for an order which will take several months so this is not ideal. It is much better to try to reason with the landlord and the agency if possible.
Examples of being misled would be if the agency did not advertise the property properly - anything which may cause you to sign up based on a false statement they made to you at the time. The other reason to unwind a tenancy would be if they pressured you in to signing - coercion or harassment and an example being, being asked to pay a deposit without having seen the property or the tenancy agreement itself.
So it does come down to whether you were misled or not (or whether it's simply you do not like the property in which case you have no rights - the landlord has to be in breach of contract in some way). If they mislead you, this is a prohibited practice and gives you the right to unwind a tenancy. If the property is in disrepair, you should give them the chance to fix the issues and failing that, ask the council to do it and they pursue the landlord for you.
If you left now, you would be pursued for the rent (for the full tenancy term) and you would lose the deposit - so my view is you speak to the agency and landlord, try to reason with them. You could use a law firm for this - they may have more success if the agency is being obstructive or if they try to disregard your rights here.
I can set out details of suitable law firms if that helps - in the meantime please see the following link for unwinding a tenancy which gives useful information :
If you have to apply to the court to unwind the tenancy, you may want to use a no win no fee lawyer - there is nothing to pay up front and you are also protected from legal costs if you lose.
Here are a few choices for you if you would like to use a lawyer (if you ask for the housing team):
1. Brown Turner Ross, tel: 01704 542002 (housing department)
2. Stephensons Solicitors, tel: 0161(###) ###-####/p>
3. Duncan Lewis, tel: 0333(###) ###-####/p>