Ideally, every one of your videos would get shot on a closed sound stage where all of the conditions could be controlled. But the reality is that sound stages are expensive, and you don't need to rent one anyways. Any area where you can close the door and control the noise level will work. If you are demonstrating a product that works outside, then go outside and shoot the video. You want to control as much of the setting as you can for your video, but you also want to make the video look natural.