Free: Contests & Raffles.
Mostly resale I guess, for the price I could just stick them in my safe and pass them on to my kid, and yes, I think Glocks are ugly as hell too.
I have a couple (couple = a lot) Glocks and if you were keeping one for yourself I would go with the 30 if it fits your hand (a bit thicker than the other 2) if it doesn't I would go with the 26. If it were for resale the 30 is worth a little more as they cost more originally and the 26 would be easy to sell. The 27 would be the hardest to sell I would say just because of the caliber (there are a lot out there from police trade-ins).