With the advent of BIM (Building Information Modeling), design and engineering firms have the ability to instantly see the form of the building in 3D. This is a great advantage to traditional 2D drawings in that you can see how everything fits together. However while the model itself is easy to comprehend it is still divorced from its context. While BIM applications can model the existing and proposed site topography along with other structures they are still abstract representations.
A 3D Virtual Tour bridges the gap between what already exists and the conceptual, virtual BIM model. It does this by combining on-site photography captured in 360˚ images called photospheres with photorealistic computer renderings of the BIM model where it will actually be.
For the most part extracting the BIM model is reasonably easy, especially if you use the right software combination like Revit to 3dsMax or ArchiCAD to Cinema4D. The problem runs into how much detail to do you want to transfer. Some BIM models contain hundreds of layers that could easily crash your 3D program or at least tax your system and decrease your productivity. You need to assess your desired output so you don't waste precious time with over detailed models. For example if you want to capture an image of the whole building from a distance uploading all the interior components like door handles, etc. would be useless.