Welcome to YorkieTalk Tammy.
It's wonderful that you are considering giving this Yorkie a loving home, and I understand your concerns. With a 2 year old unaltered male, marking is a strong possibility.
If you are willing, you could use belly bands while you have your house on the market. You would have to put an incontinence pad in the belly band, change it periodically, and remove the band to provide the dog ample opportunity to potty outdoors.
I've read here that training a dog not to mark is a challenge. Long term, this is one of your considerations before you commit.
Best wishes.