You have to register the plane before the DAR can do their inspection. Van's provides you with all the paperwork - you need to fill in your name and address.
I submitted my paperwork to the FAA, OK City, in February, and, still do not have a correct registration that the DAR can use. Trying to register my 12 as E-LSA, and, I told them so in my first cover letter to them. The first response was that the Aircraft Bill of Sale should be a Kit Bill of Sale; so, I crossed out Aircraft, wrote in Kit, and sent it back to them. Then they wanted a 'new' form filled out (I had sent a form used prior to Dec 2013). And, it has gone on and on - each request is another 30 day delay. Other 12 owners have gotten their registration in less than a month. That has not been my experience. Plan accordingly so you don't get stuck with a plane that is ready to fly and sitting in the hangar awaiting correct paperwork from the FAA in Ok City.