I replied to your thread in the PHEV owner sub-forum: http://priuschat.com/forums/prius-phev-plug-in-modifications/81900-buy-2004-prius-hymotion.html
I'm a total newbie about Prii. I'm looking at a 2004 prius with Hymotion installed. The dealer wants $12,000 US. It has 58K miles on it, looks in good shape. I drove it for 30 minutes and the monitor said I got 50.3 mpg. The dealer said he had not charged the Hymotion, but would for the next test drive. I noticed that the tires were more worn on the outside than the inside. Also - this car is a salvage from Rhode Island. They had huge rains a few months back. The dealer has a very good reputation around here so I trust him as to how far the water came up. You seem to have gone through all this before. Do you have any advice?