What size is this jacket?

It is listed as a large, and the flat measurements are 22 inches armpit to armpit, 20 inches armpit to cuff and 32 inches collar to hem. Compare those to a jacket you already own, since used garments can measure differently from their tag.

Is it good for cold weather?

It is a hooded outer layer in a workwear style, so it works as a shell over a sweater or flannel. It is not described as insulated, so treat it as a layering piece rather than a winter coat on its own.

What condition is it in?

It is described as in good used condition. Expect normal signs of wear from previous use; the listing does not detail specific flaws.

Does the hood come off?

The jacket is described as hooded, and nothing indicates a removable hood. Assume the hood is fixed.

How does it compare with a new Craftsman jacket?

You get the same workwear style already broken in, but without a choice of size or color and without a manufacturer warranty. A new jacket gives you those, at the cost of a stiffer feel at first.