The PC 690 series is a very rugged router and my personal favorite, as well as having a following in industry. In that hp range my other recomendation would be the Bosch. Both combo kits can be had for about $200 (new) as an everyday price. If you are buying used, I would want to listen to the router, and would likely also pull one , or both of the brushes to get an indication of use. Very easy to do.
The price seems a little high, but depending on the bits he is throwing in, it may be a good deal. Find out more about the bits, and you'll have your answer. If they are not carbide, they would add little to no value. Even cheap carbide bits, such as those from Harbor Freight would only add a little. Quality bits, such as Whiteside... would add significantly to the value. He could easily have his asking price just in bits. Here is where it pays to do diligence.
I am usually willing to pay 40% to 50% of what the tool would cost me new, but only if the tool is in good to excellent condition.