Short answer
A complete home inspection report should include property identification, inspector credentials, a defect summary with severity tiers, system-by-system findings with photo evidence, and a recommendation per finding. Modern reports also include a client portal and an interactive HTML version.
Long answer
Required sections, in order: cover page with property and inspector identification; executive summary of major findings; severity-tiered defect schedule; exterior, roof, attic, interior, plumbing, electrical, HVAC walk-through with photos; recommended-action list cross-referenced to each finding; signature page. State-mandated forms (TREC REI 7-6 in Texas, Florida wind mitigation, California Civil Code §1102 disclosures) are layered in for the appropriate jurisdiction.