Hi Everyone....Here's my problem and I hope someone can help me...

I need help with Housebreaking my yorkie and I am desperately looking for any advice, tips, tricks..anything. I bought my yorkshire February 10th from a pet store..They told me that he was from a family that bred yorkies for over 15 years...Well truth of the matter...the puppy came from a Amish Puppy Mill....I've read that they are hard to train b/c they live in their own waste....not only that Joey (my puppy) was started on shots at only 3 weeks...and was vaccinated around 4-5 times by the time i got him at 9 weeks. With all this said...Joey still potties in the house...everyday...i'll take him outside and wait for him to potty...but often times he wont go potty until I bring him back into the house...
I'm so frustrated...I just want to cry...someone please help....b/f i run away from home...lol
Thanks in advance~