Given that over the years there have been renumbering schemes on some roads, where houses actually change number, it's surprising that these days there are still roads where houses *don't* have consecutive numbers. I remember reading an article about one road which has three houses with the same number on different parts of the road.
Is the convention about LHS odd, RHS even when facing away from the centre of the town/village something that is more often the case than not? Or is it true only about 50% of the time. My experience is that a through road has alternate odd/even but a cul-de-sac usually has consecutive numbering.
Google Maps are good for getting you to the general part of the street, with about the same precision as the postcode: very often if you search for 123 High Street on Streetview, you can be +/- 20 houses. And searching for our house or postcode on Google gives a location about 1/2 mile away, so they are evidently using a database other than the Royal Mail Postal Address File which gets the location accurate to within a 100 metres.