We have a rescue Chihuahua cross miniature dachshund so two stubborn yappy breeds!
He's just over a year old and we all really enjoy having him however I do have a rule that he's a dog not a toy, he is crated at night and sometimes during dinner.
I've really worked on his training and got the bronze kennel club, he's never shown signs of aggression.
Loves all people and is good with other dogs, although we are careful with which ones he interacts with as he got chased into a river ( he hates water). He was off lead and a pair of springers came from no where. We are now very mindful of what dogs are around.
He loves chasing a small ball and playing tug of war, so is a very typical dog.
But I agree with others you need to treat them like a dog.
I do need to work on his reaction to the doorbell he clearly thinks it means go crazy and did jump up and nip a just delivered parcel that was in my hand the other day so the doorbell has become a trigger.
So we have just started some training on the door and will keep going until he gets it. I can see how I'd we didn't train him or would worsen but that's the same with any breed we had a gaint breed as a child and he was equally gentle but asks a nightmare with the doorbell.
One thing I have noticed is you have to keep practicing the training with them, including keep rewarding, he's not like a collie cross we had as kids who was trained then stayed trained and didn't need treats, although that could be his young age.