Advice on buying '07 Prius Touring #6 loaded

A dealer near me has a 2007 Prius Touring package #6 for sale right now with about 48,000 miles on it. It's a Toyota certified used car and I'm told has all the options that were available, leather, nav, and so on. It's a one-owner car with clean Carfax, dealer maintained with all the recall work completed.

They're asking $22,788 for it but I'm wondering what a fair price on it would be in this market? It seems like that's probably only a few hundred dollars below what it sold for new so it sounds high to me but then I've never priced a fully loaded model so maybe it's not that high. I'd love to get them down to around $19k but I'm not sure they'd go below $20,500 or $21,000 on it. Is it worth that?

KBB and NADA both show around $18,500-$19,300 or so for one in excellent condition but I don't know if that includes package 6 and all the options it has.

This car is flawless and I'd love to buy it but I don't want to get ripped off for it if I have a good chance of finding another similar one for a better price somewhere else if I look around. I'm not in a huge hurry to buy, I could potentially wait until early next year, but I rarely see a top model with all the options in this condition come up for sale so I'm trying to decide whether or not to pull the trigger on it. It's even in a color I don't hate (not my favorite but super white still looks nice to me).

I'm in Colorado, basically in the heart of Prius-central so prices here are very high because people seem to have more money than brains. I'm on the fence. Any thoughts or advice for a hopeful new Prius owner? What should I put as my price cut-off for a car with this equipment in this condition?

Also, on a Toyota certified used car, the salesman I talked to said the warranty would cover it to 100,000 miles or 2014 or 2015, he wasn't sure on the year. What are the terms on a certified used vehicle warranty? Wouldn't it just be the balance of factory? I couldn't make heads nor tails of what he was telling me on that and I'm not sure where to look for reliable information.

All help appreciated!