Considering an 07 with 117k - some questions

I posted this in the Gen II forums, but I don't know how active they are, so I'm reposting here:

Greetings all you Prius folk.

I'm looking at a 2007 Prius that I would be purchasing from a Toyota dealership. There are 117,000 miles on it now. I've driven Toyotas before, but never any hybrid of any make/model. I have a few questions I'd love to hear from you owners about:

1) What questions should I ask, beyond those I'd normally ask as a fairly experienced used car buyer?
2) How long does the electric battery last on these vehicles, on average? From looking around on this site, I've seen a wide variety of answers to this. I realize there is variability, but does anyone know an average number of miles? I don't want to buy a vehicle with 117,000 miles if the batteries tend to go at 125,000, for example.
3) Related question: how much would the electric battery cost to replace, if it were to go bad? I'm in central Virginia, if that affects cost. I've been told about $3000, but I don't know if this is accurate.

Thanks in advance for all your help!

chj4v

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