As time and the artists's effort are two of the most valuable inputs, a fair price needs to take those into account, especially since the third ingredient, creativity, is subjective and hard to pin down. Steem allows artists to start recording their beginning to work on a piece, then record the number of hours that went into creating a given piece and thus offer a credible basis for the asking price.

I don't think the market is ever going to be willing to value art based on how many hours it took. There's probably a fair way to do it, but that probably isn't it, imo. It's too focused on the artist's perspective but not on the customer's perspective - they care about how the painting makes them feel a lot more than how much time it took to make.

It can also implement tracking of the ownership transfer, through a partnership with a transporter (still hard to pull off at this point in time). This way, the UPS delivery man taking signature from the buyer that the latter has received the carefully wrapped parcel with the painting in perfect shape could automatically trigger the release from escrow of the SBD to the artist.

I like this idea a lot, even if it will take time to be implementable.