You may prefer to use call centres or large organisations, but hopefully you would prefer to use a local tradesperson for locksmithing, etc. Here are some guidelines for finding genuine local tradespeople.
If you arrived at this website from a world wide web search, you probably noticed that there are many, many "Clapham" locksmiths or "Wandsworth" locksmiths. You would find the same thing if you searched for "wimbledon locksmith" or "hampstead locksmith" and most other areas. You would also find that most of these results are all from the same handful of people trying to swamp web searches for any of hundreds of areas. Only about three of the web search results are likely to be genuinely local. (This particular page, for example, requests search engine robots, like googlebot, not to index it. So you shouldn't see this page if you are near a famous tennis venue or heath, and looking for a locksmith.)
If you are looking for a local locksmith, we really are are based in South-West London. Here we are on the map.
When you are looking for local tradespeople, look at the phone number. If a landline number were given for a local tradesperson in our area, it would be 0207 rather than 0208. If an 0800 or 0845 number is given then it may well be generosity rather than suspicious, so look for a fax number and see what its area dialling code is. If you are in South London but a supposedly local tradesperson has a Leicester fax number, then you can suspect that they are not really local. (If the phone number is an 087, or worse an 09, then, personally I would not ring at all.) (Incidentally, if you're irritated by 087 numbers as much as I am, try this website.)
If you are looking at the website of a company, such as a limited company, rather than an individual "sole trader", then they are required by the Companies Act of 2006 to display their address (and other details) on websites as well as their official paperwork.