Is this iphone compatible with Charter/Spectrum?
I believe so but it would be best to confirm with them.
yes!
I own an iPhone XR 128 gb. I am completely happy with the phone. The only thing I miss vs the successor iPhone 11 is night mode for photos.
For reference the recent Apple event dropped the brand new iPhone XR price from Apple to $499 (vs $350 here) for the 64 gb version and $549 (vs $400 here) for the 128 gb version.
The iPhone XR was launched two years ago, October 2018 as the mainstream iPhone that year (below the premium iPhone XS) and the predecessor to the iPhone 11.