IP geolocation accuracy issues?

Just launched my very first web tool, "What is My Country? - Find Your Current Country & IP Location," and I'm super excited about it! It's designed to help users quickly see their current country and IP location. As a solo founder and a complete newbie to this specific area of development, it's been a steep learning curve, but I'm really enjoying the process.

However, I've hit a bit of a roadblock, and I'm hoping to get some advice from the community. While the tool generally works as intended, I'm facing significant inconsistencies with the IP geolocation accuracy. Roughly 15-20% of users are reporting incorrect country detections. For instance, someone clearly in Canada might show up as being in the US, or even in a completely different continent sometimes, which is quite puzzling. This feedback is starting to pile up, and it's making me wonder if I'm missing something fundamental.

To try and tackle this, I've done a few things:

• Initially, I integrated a popular free IP lookup service, thinking it would be sufficient for country-level detection.
• When the accuracy issues started to surface, I switched to a different free service, hoping that a change in provider would yield better results, but the problem persists at a similar rate.
• I've looked into various paid IP geolocation APIs that promise higher accuracy, but as a solo founder with a tight budget, I've hesitated to commit to a monthly subscription without fully understanding the underlying issues first.
• I've also done basic checks on my server logs and network configurations to see if anything obvious was causing routing problems, but nothing stands out as a clear culprit.

My expectation was to achieve fairly high country-level accuracy, especially since the tool's primary function is purely country detection. The current level of incorrect identifications is concerning and honestly makes me worry about user trust and the credibility of the tool. I want it to be reliable!

Given my situation, I have a few specific questions for those more experienced with IP geolocation:

• What are the most common reasons for poor IP geolocation accuracy, especially for a small, simple web tool like mine? Are there typical pitfalls beginners fall into?
• Are there specific (perhaps even free or very affordable) databases or methods that offer demonstrably higher country-level accuracy for beginners, without requiring a massive setup?
• How do larger, more established services typically handle mobile IPs or users behind complex ISP networks (like VPNs, proxies, or large corporate networks) that often seem to cause these misidentifications?
• Is there a practical way to cross-reference or validate IP locations from multiple sources without incurring huge costs from subscribing to several premium APIs simultaneously?
• What's a realistic accuracy percentage I should aim for with a tool like this? Am I expecting too much from IP geolocation?

Has anyone else faced these kinds of IP geolocation challenges when starting out? Any advice for a newbie would be incredibly helpful!