I have an opportunity that needs a little extra money (not involving coke or hookers). We are just about to remortgage so are considering adding little to that as rates are very good. We won't be stretching ourselves, probably going from 25% to 35% LTV and the repayments won't change that much. How fussy are the banks on what that money is used for? Do I just tell them its for home improvements then spend it however I like?
They won't care; you'll be paying them more interest. The risk to them will be based on the LTV and your perceived ability to pay.
I remortgaged last year - borrowing £20k extra, mostly for home improvements and the rest to pay off any outstanding credit cards (don't come to me for financial advice :p ). They didn't want any proof or ask any searching questions but then I was being honest, if your's isn't actually for home improvements but for something else entirely they would probably at least expect you to be honest. Of course it's unlikely they'd ever find out but I'm guessing you're going against their T&Cs if you lie on the application (so could cancel your mortgage at any time) or possibly even committing an offence.
I did get asked for a rough breakdown of my home improvement costs during my phone interview (this was with First Direct) so I'd at least be prepared to do that...