My daughter was 5 going on 6 when we got our first yorkie. I would say that she knew how to treat him as I brought her around dogs at an early age but with any dog you always have to supervise .    
The cost of a well bred yorkie from a reputable breeder can be 1000-2500. That cost can seem crazy for most. Yorkies do come with certain health issues and be costly to maintain.  
Annually I would say I spend about $500 on her needs ( vet , insurance , food) but I spend much more on everything else. I save as I groom myself and limit toy purchases to when she needs something.   
I don't know how to justify the cost for you other than say yorkies are a good breed . Not for every family with children . I'm actually allergic to dogs and it was recommended I have allergy shots which are not cheap either . My yorkies don't cause me allergy flares. You got some good feedback from other members.     
				__________________   Owned by Troy(RIP) & Emma         |