Yeah, accuracy definitely varies by ISP, and region. If you'd be willing to share your IP or ISP with me (ben@ipinfo.io) I'd love to look into it and see what we might have been able to do / be able to do in the future to get a more precise location for you.
Read an article where people were coming to people's houses demanding their phone etc. because the location for that "region" was mapped to their backyard.
I find these IP lookup tools vary greatly - some will match certain IP blocks better than others.