I had a roof rack on my 2007 Prius. I used it to attach a box carrier to haul wet scuba gear. THAT roof rack will not fit the PiP. I contacted Thule, but they didn't have a Plug-In listed as one of their car models and quit replying to my email. I guess I was pestering them. I am thinking I CAN get my old carrier to work with a chain-saw, super glue and duct tape. Is the body style of the PiP exactly the same as a 2012 model? If not, which one?
I had a 2001 Prius and to compensate its lack of a roof rack, I obtained some suction cups and mounted them on the roof. Then I strapped the cargo to the door chassis. HOWEVER, the thin metal on this model resulted in some round impressions on top!! I just put too much weight on them. My new 2012 PIP does not have a chassis that juts out in a way to attach straps, if I'm not mistaken. I'm not sure how to put up a roof rack on the PIP. I did buy a receiver hitch to mount my bike rack. You might consider installing one, and buying a flat-bed rack like you see on pickup trucks to carry a big cooler or camping gear.
My roof-rack (Yakima) transferred from my 2004 to my 2010 with only a change of clips. I haven't had a chance yet to try it on my 2012 PHV yet, but there's no concern whatsoever about it fitting. The frame is the same, though be very careful with the tightening. I put two very faint dents in back not realizing width was slightly different.
