A lot depends on where and who you are buying from. In CA the only Yorkies I have seen under $1000. are pet quality Yorkies from someone breeding 2
pets. That's a lot different than getting a Pet quality Yorkie from a Show breeder or an experienced fancier who has monitored their lines for years. Not judging just stating what I witnessed.
I realize price is important, just be sure you know what you are getting. Two puppies can look a lot alike and one can be $700 and another $2000. Many (most?) of us wouldn't know the difference until the Vet bills started coming in
good luck and please don't rush.