That is an excellent deal depending on what options it has.
RX400h's were in high demand in our area when we bought and there wasn't much inventory so they weren't cutting good deals. They were asking $44k for used 2007's with 15-20k miles.
The sunroof is part of he Premium Package and/or Premium Plus Package. I believe nearly EVERY 400h comes with the Premium Plus Package, no dealers order them without it. You definitely want the Premium Plus Package and Nav. Other important options are 18" wheels, towing prep package, and the heated seats/intermittent wipers. Most dealers order 400's pretty loaded, buyers of these cars want them loaded. It's also important for resale.
What was sticker on that car? It would be around $50k if pretty well loaded.
The person that quoted me said it came with Navigation and the Tow prep package you just wrote about. The MSRP was like $49-$50K.