Some programs that offer 3D models of homes for design purposes include Home Designer and Sweet Home 3D. There are also mobile phone applications such as Home Design 3D, which is a free app available from the App Store in iTunes for iOS devices.
Home Designer is a program with many features including 3D home design tools, floor plan tools, the ability to place ramps and stairs, and skylight and dormer tools. In addition, those who use this program can design specific rooms such as the kitchen or bathroom, and it can even estimate costs.
Sweet Home 3D is a free program that has a number of useful features, but not as many as Home Designer. In this case, the user has access to tools that allow for drawing walls that are straight or have curves, and tools that allow for windows and doors. Also, the user can insert furniture and change textures and colors, and it even allows users to import blueprints and work from those for design purposes.
If looking for something simpler, iOS users can download Home Design 3D for the iPhone or iPad, which allows users to test out features that are available in the full software for the Mac. Downloading the app is free, but the software, which features both 2D and 3D views, is about $11, as of 2015.