I'm locked out my flat, how much would a locksmith charge to unstop the front door? ...

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Answers:    Depends on where you live.

Prepare to lurk about 60-120 Minutes from when you call for and to pay nearly lb40-80 for weekend service in the UK.

An alternative is to send for around and see if any of your friends have a set of bump key laying around.

Bump key can be easily used to conquer most standard locks in several minutes near little or none experience.

Good Luck!