Most of the time you look at his sire and dam, and see what health problems they have and what is down their line. Also see how their temperament is. Have his back x-rayed to make sure his vertebrae and hips are good. Cardiac test, eyes tested, and make sure he isn't a carrier for crystals in his urine. The main thing is who do you want to breed him too? Just any female? All reputable breeders will not use a stud that does not have his AKC championship for here in the US. They want a good bloodline to carry on. I you just breed to a bitch that does not show, and not a champion, then you may not be breeding to the breed standard, and there are too many of these around already. I'm not trying to put your boy down, or discourage you, just stating facts. I haven't seen your boy, so I can't say anything about him. There are many things to look at. Do you want to show him? What color is he? Does he meet the FBDCA standard? These are all things you need to ask yourself.