There are online formatters like smartystreets.com which can validate and format your international address. Is this what you are looking for? Source: over 2 years ago

What I've noticed after watching those sneaker botting videos is that they can make as many emails, proxies and debit cars numbers as they want but.... Not addresses. According to this video they mix up the way their address are written which somehow fools their system into thinking there aren't repeats even though the shoes some how end up at the same address. What these sites really need is a third party service... Source: about 3 years ago

At one point they used SmartyStreets to validate your address and if it thinks your duplex and your neighbor is the same house, they'll be treated as one so you cannot get fiber now. Source: about 3 years ago

You can give smartystreets.com a try however for that many records it might cost you just a bit. Source: over 3 years ago

A good source that is free in small quantities for all states and in the world: smartystreets.com. Source: over 3 years ago

OpenBravo POS used to be ok, it even worked with barcode readers. But you could also manually punch up a sales receipt and it would adjust on hand numbers automatically. But Open Bravo has moved on to a cloud paid model. However there a few forks from the before time, like Unicenta, but I've never used that one and can only vouch for what it was back in the day. Source: over 2 years ago

I would recommend going with https://opensourcepos.org/ or https://unicenta.com/. Source: almost 3 years ago

Unicenta works pretty well on a POS that I salvaged from a shop closure last year (no reason for doing so - just thought it would be cool to have one for the hell of it). Runs on Linux as well as Windows if you want to escape Windows Embedded 7. Source: almost 3 years ago

Looks like Unicenta is an alternative POS that can be self-hosted and is licensed as GPL-3.0-or-later. Source: about 3 years ago