Thank you for helping and trying to reunite him with his family.
My first Yorkie had a tooth abscessed through his cheek, plus several other bad teeth that he subsequently lost during his first dental care, once I found out about it. I knew nothing about a Yorkie being predisposed to dental disease & didn't know back then to brush his teeth daily and he wore no collar or ID tag (or microchip as they weren't available then) at home since I feared he would get hung up on something and choke himself. No dog was ever more loved, adored or coddled than my Scotty and if he had gotten out with those bad teeth, before I knew about the issue, been lost and on his own for a few days, he would probably look pretty uncared for as well.
I am so glad you are going to look for his owners as try to imagine how badly that person may be feeling right now with their baby out there missing. You love him after only a week - imagine if he got lost from you some day after you have had a few years of loving him. It would devastate you. I would do all that I can to find the owner and should you not be able to, you will know that you did all you could to reunite this little cutie with his mommie.
And don't just put up flyers - call Animal Control to report him as a lost dog. That is the first thing most owners do is call their local AC to see if they picked up their dog. Putting up flyers is good but what if the owner doesn't drive by that way? You can't paper everywhere with them. AC will allow you to keep the dog if the owner doesn't claim it after the designated period of time. Call some local vets offices also to report that you have found a lost Yorkie. One of them may know someone is looking for a lost Yorkie and called them.
If you get to keep him, I hope that you have him microchipped. That way if he runs out the door when you aren't looking or gets out somehow, Animal Control can find you and re-unite you with him.
