Corkage and BYO

I am very lucky, my job requires me to spend a disproportionate amount of time tasting fine wines and matching them with different dishes – often in restaurants.
The matters of corkage and BYO (Bring Your Own) often arise and over the years I have discovered that a surprisingly large number of establishments are happy for you to bring your own wine if you ask. This fact is rarely publicised for the obvious reason that the restaurant will want you to consume from their list. However, a quick call in advance or at the time of booking is all it should take.
So what should you expect to pay for corkage? £5? £10? £30?
Often the higher the perceived reputation of the restaurant the higher the price.
Recently I suggested I pay the price of a bottle of house wine in order to allow me to bring a prized bottle of Beaune Premier Cru Clos des Feves (if I had bought something similar off the wine list I would have been set back over £200). The restaurant agreed, and we reached an eminently reasonable solution, allowing the restaurant to remain well in pocket, and me to accompany delicious cuisine with a lovely wine I could afford. Although it was a shame that the restaurant in question’s website was not up to date and I could have brought something even more suitable to drink with the meal we chose…