A friend of mine is looking to get out of their flatshare. Their lease doesn't run for ages and the first break clause isn't until January, but for various reasons they don't want to live there any more. Their flatmate is okay with this and fine with someone else moving in and taking over the tenancy. They are on fairly good terms with their landlord and have just put it to them that they can easily find a new tenant to take it over.

However, they've found some clause in the lease, created by Foxtons, which suggests something like in the event of them breaking the lease, they are liable to pay 11% of the overall rent for the term, which equates to some ungodly sum.

Will this be the case? Surely young professionals move flats on short notice all the time? The landlord only cares about getting their money regularly from a good tenant - obviously my friend expects there will be fees involved in transferring it, but a fine like that would cripple them. But you'd expect it to be relatively straightforward, yeah?