I bought some aluminium sliding doors from a national window company.
Some time later I bought an entrance lockset from a national hardware store for my timber front door.
I took the keys to a locksmith to get some duplicate keys cut and handed over both the sliding door key and the entrance door key.
The locksmith said "why did you give me 2 keys. they are both keyed exactly the same."
He was correct, both keys are identical. the sliding door key opens my front door.
What is the chances of this happening?
How many houses in a housing estate have their locks keyed the same?