Go Thailand, ask the head of monks for 2 of his finger nails.
Approach Vacheron Constantin and commission them to design and craft 2 watch with Lunar Calendar, tide & moon function. Ask for enamel dial and pass them the fingernails. Get them to find a way to have the nails integrated onto the dial and that the dial should be auspiciously design as blessings for Longevity.
have the image of the current thai King engraved on to the caseback
Tell them you want to remain anonymous, and that they only have to record it as a birthday gift to the king & the name of the monk whose nail is embedded
When done, pass one of the watch to the monk for him to gift it to the King during the king's birthday.
Keep one for yourself. 8 years after the King & Monk pass to Heaven, put the watch up for auction. Get a few of your family members to bid for the watch separately until u reach a value 10 times more then your investment. By now you have already achieve 10 folds and the value is official
Keep the watch for your grand kids, value will have multiple fold as years pass
Meanwhile, you can wear the watch to start the patina process if you so desire
Not enough money to pull this off now? then start saving $10-$20 a day, you'll reach there sooner or later. Don't waste time on othersif monetary value is what you're gunning for.