Markham Lock & Key Service is a licensed locksmith that is proud to provide 24/7 locksmith service. Commercial, Residentiaan and Automotive Locksmith Service. Emergency Locksmith Service - 24 Hour Service. Services: lock installation services, lock repair service, lock change, rekey locks, master key lock system, high security locks, key cutting, door repair, file cabinet locks. Markham Lock & Key Service - locksmith in Markham, Thornhill, Stouffville, Richmond Hill, Scarborough.