Nemsisisnight - 12 ft is 5 lbs (10%) heavier, 1'5" wider. The extension is the same 8'2". The 12ft is $100 more than the 10ft.
The awning comes with all the items you listed, including the center rafter and mounting hardware.
re: 12' on an EB - I am not a fan of installing these on our vans with the brackets. And , if the van has a passenger side ladder it creates roof access issues. Additionally, The brackets were really designed for the 10ft unit. If you have your heart set on a 12 ft with my brackets, it is at your own risk. The bracket set includes three brackets.
Now on your B190 style, I think you would have to mount the awning to the top. In that case you would use the Fiamma supplied mounting kit and your only issue is going to be the curvature down the side of the top.
dig255 and gcvt - Please open up your awnings and find the sticker with the model number. It is on one of the arms. Please take a picture of it and email to me at firstname.lastname@example.org
. The caps are $20 to $30 each depending on the awning model.