Ask HN: Recommendations for privacy-respecting medical patient portal EHR SaaS?

Hi HN, I'm volunteering help for medical organizations including small-town U.S. doctors and dentists. I'm encountering many technology issues relating to small-business electronic health records (EHR) software as a service (SaaS).

I'm seeking recommendations please for privacy-respecting small-business EHR SaaS.

Must have: sign up a patient; schedule an appointment; send a bill via email; maintain notes; comply with HIPAA, GDPR, CCPA.

Should have: patient portal sign in; save payment methods; messaging among providers and patients; set recurring appointments; import/export EHR into exchange formats such as JSON, XML, CSV, PDF.

I have 100+ companies to evaluate, so I'm seeking HN guidance on any direct perspectives and experiences please.

I'm seeking a service that is not owned by private equity, and that does not sell/share/market patient information.

Thank you in advance for suggestions!