I'm currently doing the World of Luxury Quest for the 2nd time and I discovered that placing the TWO luxurious vessels in my sims' house BOTH gave me 125 deluxe coins per vessel :eahigh_file:
Both also replenish coins after 11 hours.
So that means I get MORE & DOUBLE deluxe coins from the vessels for opening ornate boxes.
Hope this helps anyone. Happy Simming!