Hi Mr Magoo
Typically most car valeters are just that clean and valet. Some are very good others just on the same level as a £5 car wash.
Detailing as a term really comes from Stateside, but the quality guys use this term, and they ultimately detail every part of the car, again theres good and bad, the best are 'anal' and very expensive but the result can be a finish far in excess of what the car was like even when delivered new. (It often comes with a number of paint issues and swirl marks etc). Time for prep can be from a few hours to a few days!! The equipment and materials they use are probably not viable to the average owner to purchase, but I am looking for a real top level finish, so in for a pound in for a penny so too say.
I have been recommended a guy in Kent, and after a long discussion with him, feel pretty confident in what I am going to get, if anyone is interested then let me know and I will keep you updated as to the result and if it was worth the dosh.