In the spirit of Jeff's brilliant 5-4-8 discussion (best five watches for $8000, no thought to resale) I'm proposing a related and oppostie challenge:
Coffee Can Chrono
Here are the rules: You get $1,500. You've got 10 days to go out and buy a watch or watches.
The watch goes into a Ziploc bag, the bag into a Maxwell House coffee can and gets buried in the back yard.
In five years, we dig up the watch, Whichever watch can be sold for the most within the same 10 day period is the winner.
This is almost the exact opposite of 5-4-8, where one of the stipulations was that you had to wear/collect the watches but gave them back after five years, so resale wasn't an issue. Here, you don't get/have to wear them, so resale is the only issue.
The 10-day time limit is designed to limit the choices to reasonably common models--i.e. that you can't circumvent the low budget by spending 1,000 hours searching for a tremendously obscurew watch or a killer deal on the buy side or the one guy on the planet who'll buy this watch when it's time to sell. For the sake of the gam, imagine that you'll be paying low retail for the watch on ebay, a dealer, or through a private sale, but you can't wait for the bargain of the year.
Other than that, the watches can be old or new. Heuer or non-Heuer. One or several. Minty or user grade, chrono or non-chrono.
Good luck, and happy digging.
best
Allen