I think the idea about mint AC chips is a wise one, particularly since it does not require a lot of research time into old chips, fake chips, or rare chips. I would offer a few other suggestions related to that.

First, I would stick with AC chips purchased at face value because they can't go down in value under current law.

Second, I would stick with fractionals or $1 chips, because fractionals always sell for a premium. $1 chips usually sell for at least $1 each. $5, $25, $100 chips often sell for fractions of their face value and don't have as many collectors.

Third, I would buy the chips from the casino the week it opens (or the week a new rack is introduced) so condition is never an issue. Buyers pay a premium for chips in mint condition.

Fourth, following that strategy, I'll bet you do better than 10% per year: you can turn them around in 2-3 years and double your money by selling them for $2 each - not an unreasonable price for a mint condition chip as a new release or after a casino has been open a few years and its current chips get worn down. It might not be as profitable to dump $1000 worth of chips on the market at the same time, but you catch my drift, I'm sure. You could always trade with other collectors for racks of mint chips from other casinos to enhance your inventory.