For Tim, if you do want euro then you can get double cylinders that allow
unlocking from the outside with the key inserted inside but they are the
exception rather than the norm. I can't for the life of me remember the
term used to describe such cylinders but a locksmith will know what you're
on about and should do supply only, they're an easy fit.

Cylinder with thumbturn is the general term, in premises such as hotels &
guest houses the fire officer usually insists on them.
On external doors in private properties the insurance companies are a bit
iffy about them, if someone breaks in through a window for instance, they
can open the door from the inside and let their mates in and escape easily
with the loot.