Whenever clients (usually interior decorators) appreciated accurate color rendering I used a WhiBal G7 grey card. These are low reflective ,scratch, fade, and water resistant plastic cards.
Once the lighting for a scene was established, I would take a set of photos with the WhiBal card in different lighting locations. This enabled selective white-balanced rendering of raw files as I could determine the optimum color temperature for different regions in the scene. For specific interior features or products I could often get away with placing the WhiBal card near the object of interest.
When you let direct off-camera lighting dominate, color balance in post production is straightforward. However, usually quite a bit of time is required to modify the light so the final image does not have a harsh, high-contrast look. So, I used I used existing and multiple off-camera flashes to light scenes. The off-camera flashes were used at the lowest possible power to even out the scenes' illumination. Often they were used to bounce light off of walls and, or ceilings to soften the light. The result was regions with multiple light color temperatures(daylight, tungsten, halogen and flash). Flashes can be gelled. Gelled flashes don't work well for bounced light because the surface changes the color temperature. Gels also reduce flash output and increase the time required to optimize flash location.