IP lookup accuracy issues

hey everyone, so a few weeks back i posted about our ip location data being totally stuck, which was a nightmare. thanks to some great advice here, we got that sorted out and data's actually flowing now, which is a relief.

but, and there's always a 'but' right? now that it's flowing, we're seeing a huge problem with ip lookup accuracy. like, seriously bad. we've got users in new york showing up in ohio, or people in san diego somehow ending up in san francisco. it's not just a little off, it's completely wrong for a significant chunk of our users.

this is really messing with our internal analytics, especially when we try to segment by region. our regional targeting efforts are basically useless because of this, and honestly, when we try to personalize greetings or content based on location, it just looks unprofessional and kinda creepy when we get it wrong.

what i've tried so far:

• we're currently using a pretty popular free ip geolocation api.
• i've gone through their docs a few times to see if there are any obvious pitfalls or known limitations, but nothing jumps out that would explain this level of inaccuracy.
• i've also started looking at paid ip location services, specifically maxmind, as they're often recommended. but i'm a bit hesitant to just jump to a paid service without knowing if it'll actually solve the core accuracy problem or if it's just a more expensive version of the same thing.

so, i'm really wondering what the best practices are for improving ip lookup accuracy for a saas, especially for users within the US? are there particular ip location services or apis that are known for significantly better accuracy, or is it just a trade-off we have to live with? and finally, any clever ways to validate or 'clean' inaccurate ip location data before it even hits our database? like, some kind of sanity check?

really need some expert advice on this one, it's becoming a pretty big headache. thanks in advance for any insights!