I have my dogs hips certified thru OFA because it is more convenient for me where I live. I would have to travel quite a distance to find someone to PenHipp. With that said, the price for everyone is going to be different depending on veterinary costs in your area. OFA preliminaries are 25.00 and certifications are 30.00 for hips, then you have your vet costs for the x-rays and anesthesia which will vary depending on costs in your area. Prelims can be done as young as 4 mos but it is best to have prelims done around 12 mos. Dogs can't be certified until 2 years of age.