Back inside without replacing the lock
Most lockouts we see in London are a spring latch that snapped shut behind someone, or a deadbolt turned from outside out of habit. A latch can usually be slipped or picked in minutes. A locked deadbolt takes a little longer, but standard Kwikset, Weiser and Schlage cylinders almost always open without a scratch.
Apartment and townhouse doors often have heavier lever sets and steel frames. We open those as well, and if your building has a superintendent or property manager on call, we work with them so you are not left waiting in the hallway.