Use the price search to find the current compound row, then open its canonical owner for the full package and normalized-price comparison. Forms, entities, and incompatible units remain separate rather than being collapsed into one cheapest claim.
Keep price and vendor evidence separate
Package price, normalized cost, quality review, testing access, shipping, payment, and freshness are independent fields. A coupon can change current value, but it cannot improve a vendor's quality order.
Verify the exact listing
Confirm the product name, form, strength, package quantity, stock state, destination, payment method, mandatory fees, shipping charge, refund terms, and final total on the current vendor page.
Match evidence to the lot
A general testing library is not automatically evidence for every product. Match the exact compound, strength, lot, laboratory, report date, method, and reported result, and leave untested categories unknown.