Northern Rock - Consent to let - Any advice?

Hi all,

I have a resi mortgage with NRAM. They have told me I need consent to let; fair enough.

They want to charge me £750 for the priveledge of doing so though!?

So I have a couple of questions;

1). Has anyone experienced this; what did you do?
2). Is there a way to reduce these fees?

Any advice gratefully received!

Thanks