Single-location dental practices or vet clinics are always best served by off-the-shelf PMS (Dentrix, Eaglesoft, ezyVet) at $299-$999/mo. Mid-size groups (5-30 locations) benefit from cloud options (Curve, Henry Schein One, Provet Cloud). Custom builds pay off for large DSOs (Dental Service Orgs) and VSOs above 40-60 locations or $50M revenue where unified reporting, payor-mix analytics, and multi-location clinical workflows drive margin — break-even vs Henry Schein One lifetime cost is typically month 26-34 at 50+ locations. Teledentistry and telemedicine-vet startups win on custom because the consumer-facing UX + clinical-integration layer isn't what legacy PMS optimizes for.