What would be the cost of a darkwood collapsible plank?

[shaxberd]

It occurred to me recently that a collapsible plank made of darkwood would only weigh 5 lbs. and could therefore be manipulated into place with a Mage Hand spell. Could be useful for getting across pits or even barring doors shut. The rules for darkwood say that you have to add 10 gp per pound to the cost of a masterwork version of an item, but there are no masterwork collapsible planks. So what would the cost be? Most other masterwork items that aren't weapons or armor seem to default to 100 gp in cost.

[seebs]

Tools are +50gp, I believe:

Artisan's tools, common 5 gp 5 lbs.
Artisan's tools, masterwork 55 gp 5 lbs.

I'd probably file it under "tools".

[Ciaran Barnes]

Is the plank collapsing through magic? Does it fold on hinges?

[Aureate]

Ciaran Barnes wrote:

Is the plank collapsing through magic? Does it fold on hinges?

It folds on hinges.

Link to prd entry

I would price similar to tools as well.

Normal price: 4sp
Masterwork: 50GP (dropping the 4sp for rounding)
Darkwood version: 150GP (masterwork + 10GP/pound for darkwood.)

Edit: to go from common to masterwork, I looked at backpacks as an example. Common were 2GP, masterwork are 50GP.