Keep the arithmetic exact
The selected reference tickets are 425p, 2840p and 1790p, totalling 5055p. A confirmed merchandise-only credit of£50.55 leaves zero merchandise. A£50.56 credit is one penny too large and is rejected. This does not establish entitlement to a voucher or discount.
Additional charges remain separate
With a full merchandise credit, hypothetical entered delivery£4.99 and additional tax£1.25 still produce£6.24. These are validation inputs, not actual merchant fees. Blank or invalid charge fields withhold a full total. Included VAT must not be added again, and no tax rate is assumed.
Input bounds are deliberate
Prices accept nonnegative GBP amounts with at most two decimal places and a maximum of one million. Offer quantities are whole numbers within the same bound. Scientific notation, extra precision, negative values and blank required fields are refused. £0.10 times three remains£0.30, and£47.99 times two remains£95.98.
Use it as a purchase record
Replace a reference ticket with the actual selected checkout price when it changes. Keep the exact format and price basis with the entry. The site does not submit payment details, forecast reorder frequency, allocate a price to painting quality or calculate chemical recipes.
Sources & scope
Checked November 5, 2026. Manufacturer and retailer references support the specific statements. Dated displayed prices are not final checkout quotes, performance rankings or performance testing. This shopping reference does not replace the exact product label or retailer instructions. Current received labels and independent art-material/chemical/content/commerce review remain pending.