When choosing a lock here are a few things you should consider
- Is the lock Compatible for the door or window you wish to install it on
- is it a known and reputable brand
- does it meet the correct specification for the door or window (BS3621:2004)
- is it within your price range
Some locks can be installed by yourself but locksmith local would recommend you get a locksmith to install most locks as a bad fitment may jeapodise your security.