I model everything in Maya since it's what I first learned and have been keeping up with it as it evolves. I haven't found anything else really that makes modelling easy so I just stick with it. As you can see here I have my cargo train model that I'm going to put into the matte. Everything is named properly and cleaned up - history has been deleted and everything has been centred since it's not going to be animated.
Here I have my UVs layed out and ready to be textured. Not the best job, but depending on how close we are going to see the model or what it's going to be doing depends on how much effort I put into the UVs. since this train will be static and you'll only see one side, it's a very quick UV job.
I have now imported my model into C4D. Like all CG programs, some have their pros and some have their cons. I like C4D's easy texture building aspect and it's a nice program of keeping everything simple. Now that I have my model, I duplicated it as needed. I did a dirty job of texturing using my prior cargo textures (will be changed later) just to get a nice visual of what to expect.
Finally, putting it together in photoshop. This is an actual 10 second shot but for now I'm building the still as a reference guide for when the footage is good to go. Placed the train in its proper position and bam, just like that. I removed the straps from the train as they were way too white.. and after seeing a few trains go by at yesterdays music video shoot, I didn't see too many trains with straps.
Here is the progress so far: