Room Arranger is small and compact piece of software. Still it lets you design nearly anything you imagine. Once you understand the basics it's easy to bring it to next level. Nearly all functions have keyboard shortcuts, so you can learn to be pretty fast in Room Arranger.
Room Arranger will not only let you fly around the scene, but you can also walk through it like in reality. There are nearly 300 objects in the standard object library. Furniture, and other equipment. For each of them, you can modify their dimensions exactly as you need - you are not limited to what we think is the most common.