One word, ..........rarity. Ok, two words....... popularity. Rare will always command value, as long as it has a desirability factor. But when you have RARE and POPULAR together, an item will significantly increase in value. For instance, a really prime Rogers 16x16 in 1965 Sparkling Silver Pearl..... might hit 350-450 on a good day. A 14x14 in the same finish, and prime.... +1000.00, several have recently sold above a grand, with one at 1475.00 plus shipping on Ebay.
If you get lucky and are hooked up with a 14 any where under those prices, its a good deal. If you are the lucky dog that picked up the Rogers 14 from the recent Chicago (i think) craigslist offering at 40.00, it would have been a good day to buy lotto tickets too.
I paid 3 bills for my Rogers 1966 Sparkling Blue Pearl 14x14. It has some minor issues, but is clean and worth much more than I gave for it. The guy looked at me like...... I got a live one, Sucker....... and me. ... well, I looked at him and thought, Thick, really thick. I drove a hundred miles for that drum.