FreeCAD - An open-source parametric 3D modeler
Modsy - Interior Design You Don't Have to Imagine. See your exact room, expertly designed in 3D with actual pieces of furniture from well-known retailers that you can buy on the spot.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Klapty - Create and share your virtual tours for free or have them done by a professional photographer. Klapty - The world in 360 °.
Onshape - Onshape is the first full-cloud 3D CAD system. It runs in a web browser and on any mobile device.
VirtuallyShow.com - VirtuallyShow.com is an online affordable and feature-packed virtual tour service that allows you to create your residential and commercial real estate virtual tours in just a minute.