About Us. Collin Testing is a psychological testing practice in Asheville, NC, offering comprehensive diagnostic assessments for children, adolescents, and adults. We are now expanding our commitment to specialized, evidence-based care by launching our dedicated therapy services division. We serve a diverse client base, including many individuals who are neurodiverse (e.g., ADHD, Autism Spectrum Disorder). The Opportunity: Be Our Founding Therapi...