Like the two above suggested, wait for one with low Km/milage BETTER..
Well, unless you live in small "3rd world" country BikeWise like I am (Middle-east Hollyland..) - K12's (R,S & rarely GT's) there are abit more than few sold (the dealer then was pricing the bikes with multy-premium high-as-hell price tags..), and with the gear issues the model got notorious with very bad taste plus high expences on service.. The K13 that came after it sufferd from the previous model BAD reputation, so even less bikes sold from '09 to '15 when the factory stopped its prod.
I guess that you can count the K13's TOTAL (S, R & GT's) less than a dozen on the roads today here.. So, when you can find one that is for sale, especially the K13S or R (the GT is less desired) you should grab it, ever if it has nore than few ten thousands KMs. Here many bikes are everyday commuters, so most of them have pretty decent milage on them, or if they use as a weekends tuorers they are in use most of the year, because the weather is mostly nice with few rain days a year.