Sure Karl,
I used ArchiCAD for modeling, Cinema 4D with Vray for light, rendering, landscaping, people and cars.
For the vegetation, I used 3D trees with Vray Proxy, otherwise, it would take forever rendering or crash. Vray Proxy is a feature that allows you to bring external references of high polygon objects without adding lots of geometry into your project, kind of like "module" in ArchiCAD.
I do not remember the exact time of the rendering... could be around 2 to 3 hours max in a Mac 2x3 GHz Dual-Core Intel Xeon, 9 GB ram (4000 × 2250 px)
Just little post production to enhance light and colors.
About commercial textures. It takes time building your library. Mine has textures from so many different brands: Vray Materials that come with the plugin, Texturama, Dosch Design (just a very few Dosch textures are useful to me) and Turbosquid. Many of them have been tweaked to get rid of unwanted patterns and others created by myself. This could be time consuming, but I specialize in architectural visualizations, so it is part of my job to get them right. Finally, materials in Vray have many layers, so it is not all about the textures when you are creating them.
All the best!
Diego