It sounds like the bloodwork through your vet may be a bit pricey, but overall that really isn't that much.     
Starting at age 6 or 7, they need bloodwork (blood panel, CBC, and thyroid is good too) at least yearly.  Then heartworm testing yearly, fecals twice yearly, urinalysis at least yearly...  Maybe the eye testing was quite a bit?  Dry eye (KCS) is genetic (and common) in Yorkies, I think.     
				__________________  Crystal  , Ellie May (RIP)  , Rylee Finnegan  , and Gracie Boo🐶      |