Who I have the same questioned this topic

I purchased a new iPhone 6s plus a few weeks ago and I have never had accurate GPS on the phone. I am new to this area and rely heavily on maps, Waze, or Google maps to get me where I'm going. Since my GPS is unreliable, those services frequently being "rerouting" while I'm driving because it thinks I'm a mile away from where I actually am. Super frustrating to say the least. I have seen lots of threads on this problem, but would benefit from a step by step diagnosis to make sure I'm covering all the bases. I haven't taken any action yet on my side besides making sure my location is on for all of those wayfinding apps.