I am getting an autofill, and when I asked my PB whether that was coming with a backflow preventer he said no. Although it may very well be required by Code (and perhaps he was obligated to give me one), he told me he would install one for $100. I agreed. My question is whether there are different versions or varieties, and if anyone has a specific recomendation for one. I would offer my PB more if I thought there was a better one than the one he is giving me because I think this is very important. I haven't yet asked him what I am getting, so I don't know his plans. Below is a picture of the pipeelading to my hose bib. As you can see he hasn't hooked it up all the way to the bib yet.