Renders: visuals / color plans / materials
Taking the "Interior Design · Space Render" template as an example: about 5 credits on Seedream 5.0 Lite.
The credit prompt before each generation is authoritative; it changes with model, resolution and duration.
Floor plan or description of the space · What you need (render / coloured plan / materials).
A single generation usually lands between one and a few minutes depending on model and resolution; several can run at once, with the limit set by your plan.
Yes. Any shot can be re-run with an edited prompt or a different model; what you already generated stays, and re-runs are charged at their actual cost.