12-product 1:1 grid: Seedream v4 $0.39, 4.5 $0.60, 5 Lite $0.525

Twelve square product tiles cost $0.39 on Seedream v4 ($0.0325 each), $0.525 on Seedream 5 Lite ($0.04375 each) and $0.60 on Seedream 4.5 ($0.05 each) through Sume. The Image API docs list the billable per-image prices, which are Sume's list price x 1.25. The 5 Lite price sits between the two others, which makes it the odd order: the newest of the three is not the priciest.

The $0.21 gap between the cheapest and priciest is real money only at scale; at 12 tiles it is the price of two extra Seedream 4.5 images.

What does the grid cost at each size?

Same prompt template, 1:1, one image per tile.

How do I choose?

Render the same 4 SKUs on all three, hold the prompt fixed, and compare. If v4 passes, the cheaper model wins; if you need the finer result, step up one model, not three. All three take up to 10 references and n up to 4. Prices here are list x 1.25 in dollars per image before whole-cent rounding; the catalog's billable formula reads "list x 1.25, ceil usd cents", so confirm the first charge in usage.cost and budget from the invoice, not from the sum.