NES Test Carts?

[Tupin]

How often do these things show up on eBay/are found in the wild?

The rarity guide lists it as an 8, but then it says it's worth about $80.

[jeffg]

there are different ones which are rarer.

The Zelda Yellow Test Cart is probably the most desireable one. There supposedly is a Duck Hunt one but I think only 1 or 2 have been seen.

The Zelda one was selling for $600 plus at some point, they have cooled down to about $400

I found one at a flea market for $2, with the label half torn off. I sold it for $350 last spring

[Tupin]

there are different ones which are rarer.

The Zelda Yellow Test Cart is probably the most desireable one. There supposedly is a Duck Hunt one but I think only 1 or 2 have been seen.

The Zelda one was selling for $600 plus at some point, they have cooled down to about $400

I found one at a flea market for $2, with the label half torn off. I sold it for $350 last spring
What about the ones that test the controllers/system itself?

[PapaStu]

A couple hundred, depending on condition and the breeze on ebay.