My yorkie Bentley was neutered at 5 months old. He always squatted like a female to pee and he never marked until he was over a year old and we rescued our chihuahua, Cha Cha, who incidently wasn't spayed! (Thanks for that info Yorkie Rose.) Now he's 2 1/2 and he still squats when he pees, and even though Cha Cha is now spayed every once in a while he'll hike his leg to mark!
Thank goodness it's mostly outside!