My approach for the interior render speed up. This is a starting setup. You can increase the sampling and get a perfect result for just a little bit longer time, than I described in the video. Or you can lower the samples down to 0 and create a very fast previsualization for any animation scene - 15sec per frame or so. Depending on the scene. I can make another video about the Barbershop scene, if you'll be interested in. It's basically the same setup, but it's lit a little differently.