Miles' explication ( sorry its so late)

The discovery of the treasure was like a deflagration. Instead of returning to Rome with the sudden Fortune, which has been his dream maturing into misery, Jose Arcadio converted the house into a decadent paradise. He replaced the curtains and the canopy of the bed with new velvet, and he had the bathroom floor covered with paving stones and the walls with tiles. .. ( too long to type the rest)

As we find out in chapter 18, Jose Arcadio finds treasure in Ursula's old room.  With this newly equipped wealth, Jose Arcadio makes his house into a paradise.  The house throughout the chapter goes through a transformation in which the house goes from covered in plants and forest into a luxurious mansion. He  has a party at the Buendia house, just like how there used to be parties there.  Although it is a celebration, the party does not feel the same as the parties once were because this party does not have happiness, Jose Arcadio is just expressing his wealth. However,  this party can still  be interpreted as a "turning point" in the book in a way because none of the people of Macondo have been happy since the floods came.  This is the first time that we have  seen anything involving happiness in several chapters.  With the use of symbolism and the reoccurring theme of memory, Marquez uses the characters and the house to symbolize the state of Macondo and foreshadows what lies ahead.