When Yu Hong asked for a house, the audience didn't understand, but considering Hong's situation, it was probably her hope. Her husband died, her son was not around, and she had no money to buy a house, so there was no way to ask Zheng Juan.
If Yu Hong hadn't come to Zheng Juan to ask about the house, Zheng Juan didn't know that her little house could be so useful. After many twists and turns, Zheng Juan couldn't bear to see Yuhong homeless. Later, he thought it would be better to catch up, so he discussed with his son and transferred the house to Yu Hong.
I have to say that Zheng Juan's family are all good people, and her son Cong Cong followed the parents' good intentions, preferring to rent a house by himself rather than let Yu Hong suffer alone, so he gave the house to Yu Hong.