A render is a picture. Interactive 3D is the model itself, running live in the browser. The visitor drags to rotate it, clicks a color, opens a panel. Nothing is pre-rendered, because the product is being drawn on their screen sixty times a second by the same kind of engine that runs a video game.
That distinction is the whole value. A configurable product with six finishes and four handle options is 24 photographs, and that is before anyone asks for a second angle. As one model with the options wired up, it is one build that covers every combination, including the ones nobody thought to photograph.
There is a real constraint, and it is worth knowing before you budget. A render can be as heavy as it needs to be, because it only has to finish once on our machine. A browser model has to load on a phone over cell service and stay smooth while someone spins it. Engineering geometry is almost never ready for that. Converting it is most of the work, and it is why the model conversion is quoted separately from the build.