Is it obligatory for a son to send money to his well-off parents who spend their money lavishly, while he is in need of these funds? And would Allah be pleased if the parents sold all their possessions without helping their son who does not own a home?

A son is not obligated to spend on his parents unless they are in hardship and he has surplus wealth for their maintenance. However, showing kindness to them is required. Relatives should be advised against blameworthy extravagance. It is not permissible to deprive any heir of their share unless they willingly give it up.