Tax-exempt resale cert workflow, per-state forms (CA BOE-230, NY ST-120, FL DR-13)?

Cosmetology professionals reselling products to clients can claim resale-cert tax exemption. Each state has its own form; Magento needs a workflow per state:

• California, BOE-230 General Resale Certificate. Customer fills + signs + uploads.
• New York, Form ST-120 Resale Certificate.
• Florida, DR-13 Annual Resale Certificate.
• Texas, Form 01-339 Texas Sales and Use Tax Resale Certificate.
• Illinois, Form CRT-61 Certificate of Resale.
• And ~40 more, most states use a Streamlined Sales Tax (SST) multi-state form, but the “big four” (CA, NY, FL, TX) require their own.

Architecture: cert upload form on the customer account page, per ship-to state. Form file uploaded to encrypted S3 (or local encrypted storage with audit log). Expiration date tracked per cert; auto-renewal email at 60-day warning. Magento tax classes auto-route exempt customers to the zero-tax rule when shipping into the exempt state.

The reporting: state DORs audit you 1-3 years out. You must produce, on demand: the cert PDF, the customer’s state license number, the order list shipped to that state with tax not collected, and the dates. Magento order tax reports + customer-attribute reports cover this if architected from the start. Bolting it on later is painful.

Per-state DOR rules change occasionally, CA updated BOE-230 → CDTFA-230 in 2018, NY ST-120 has multiple variations for different reseller categories. Quarterly DOR rule sweep on retainer.