1. The 5" is my favorite but the shorter 3.5" version is sexier and that's the one that commands big bucks in the used market.
2. No box and 90% takes it out of the realm of high priced collector guns.
3. Prices will vary wildly and all you will get is guesses. If it were my friend asking me what I would offer, I would offer $650. A good price for me, not a rip off offer, and if he thinks that it's worth more then let him name his price and let the buyer decide. My guess based on what I've seen selling around here is $700-$900 so my $650 offer assumes I get the "you're a friend" price. He might figure I'm not that good a friend...