Hmm, 6-qt Fagor Duo pressure cooker, $85.

Dried black beans, $1 - $2/pound.

Can 15oz black beans containing 1 1/3 cup drained beans, about $2.

2 cups dried beans yields 5-6 cups cooked drained beans.

1 pound dried beans = 2 cups dried beans.

Rinsed, un-presoaked black beans cooking time: 25 minutes, after maybe 5-6 minutes of bringing it to boil and reaching pressure level.

Cooking time for can of beans: 5 minutes.