Since there are still brand new ones being sold on ebay, and probably Case stocking knife stores, the value of the one you have will never be greater than what the knives are priced by the sellers. Once the 500 have been sold to the first round of buyers the value of the knife will be adjusted by what the secondary market will pay.
Example: Knife A was made in a batch limited by the manufacturer to 100.
Suggested retail was set at $250.
Retailers that bought the knife from manufacturer (or wholesaler) discounts the knife 30% off to retail to move them, set price is $175.
If you buy one at $175 you will have a hard time selling it for that price until the original retailers have sold the entire batch of knives.
Once the knives are sold out they become "vintage, collectable" and the price will be what the market will bear. Some knives will go up in value, most go down. Feel lucky if the knives you buy maintain their value and you can resell them for what you have paid for them.