Licensed Mental Health Professionals — Verify that the provider connects you with a licensed mental health professional. Live Consultation — A legitimate service requires a live consultation via phone or video. Registry Fees — Avoid providers that offer to register your ESA for additional fees (outside of the cost for the legitimate letter from a certified professional), as there is no official ESA registry. Money-Back Guarantee — Reputable providers often offer a money-back guarantee if your letter is not accepted. Positive Reviews and Testimonials — Check reviews from other customers to gauge their experiences.