Its actually illegal (I assume everywhere but def here in VA) to not have house numbers that are easily visible from the street for fire or police reasons. They actually say we have to have contrasting numbers with background combo, but so many times I see brick mailboxes without numbers at all, or someone who painted the mailbox post and the numbers the exact same color like white and cant even read it in the day time let alone at night. I mostly rely on the people who are smart enough to number their houses correctly, count down or up to the house Im delivering too, and then use MapNav to help me get within +/- 1 house. Still a pain in the ass
Yup, but obviously not a high priority for enforcement. I've gotten at least 5 people to post legible house numbers over the past year on various routes. If you make contact, it never hurts to give a friendly nudge -- people want to get their smile*.
As far as I understand USPS has authority over issuing house numbers, and while you can usually infer well enough based on the pattern, there are discrepancies ... the more remote parts of my route have several. Evens/odds suddenly flipped, numbers out of sequence, etc. Mapnav would have me misdelivering a couple times a day haha. But I'm also not gonna bother trying to get the dispatcher to fix these and deskill the job further. The longer you cover routes, the more you start to understand the glitches, e.g., mapnav is useless in new subdivisions, hit and miss on rural stops, and never trust when it would lead you down a long driveway that you'll find somewhere to turn around without rutting up the grass.
I've never shied away from opening mailboxes if I can't verify an address -- usually, but not always, USPS has marked the house number inside the mailbox. Definitely a pain in the ass after dark, even with a good torch.