You can purchase a USB to cigarette lighter socket on Amazon for about $6. Then you probably will have to mount your detector in the lower right corner of the windshield to avoid the coating on the windshield.
I don't know the answer to that question, but you scared me enough that I just went out and tried it in my wife's car (I don't have my Dream yet). Anyway, the USB to lighter socket worked just fine with my Valentine radar detector. I'd much rather hard wire it but it does appear this solution will work. The technicians at Millbrae told me to definitely try mounting the detector in the center of the windshield first and then if it doesn't work properly mount it over in the lower right section. Once I get the car I'll see how it works. Almost all of the highway patrol in the area use radar so I'll be able to tell if it works or not.