Is it possible to use the command line to render several different blend files?
I would like it to render the first .blend file, and then move onto the second only once the first had finished, and then onto the third the fourth etc.
Is this possible? 
you can do a shell script, i you are using unix you can use a bash file, or if you are using windows, you can do a batch file
You can do that from the sequencer, if the render resolutions are the same.
Just append the scenes you want, and then add them in the sequencer …
You’ll have to set the scenes to start and end frame1, for stills.
Hope that can help you …