Non Destructive Door Unlocking

I have a standard key-operated cylinder lock on my front door. The door simply closed behind me and latched, so it is shut but not actually locked; the key is sitting inside on the other side of the door... (Budget: $30 - $250 CAD, Jobs: Handyman, Hardware Security Module, Installation, Locksmith, Physical Site Survey, Security Auditing, Security Systems, Troubleshooting)