Question:
The client might lose at cards, and the gold cigarette case with sapphires would be sold back to Cartier, who would promptly sell it the next year to another gentleman.

Does it follow that "The client may not win at playing cards."?
Answer:
yes

Question:
We have never needed one.

Does it follow that "We have never needed one of those."?
Answer:
yes

Question:
Caravaggio's only still life, Bowl of Fruit, is here.

Does it follow that "Bowl of Fruit was the only still life painted by Caravaggio."?
Answer:
yes

Question:
To avoid possible complications with customs, veteran travelers ask for and retain a receipt (sales slip) for everything purchased.

Does it follow that "Veteran travelers keep their receipts to avoid complications with customs."?
Answer:
yes