To me, it really depends on why you want to know, LOL!
If the stay is just for my family, I don't calculate the cost at all - the "calculations" were done before we purchased. At that time, we determined that
DVC would be a good economic value for us, considering the way we vacationed. Now I just remember that it turned out to be the way to go for us.
If I'm going to rent points or consider a non-DVC option, I calculate the value of the stay at $10/point. That seems to be the average "market" value of the points.
If I'm "sharing" DVC accomodations with friends or family and they inisist on paying, we generally just have an argument that I always win. I let them buy the groceries or a nice meal out for everyone in lieu of paying for the accomodations if they continue to insist and most do, LOL!
If I am just talking to friends/acquaintances about the value of DVC, I often quote rack rates for the DVC accomodations. If I happen to know that there are code discounts available for the DVC rooms (and I have been surprised that often there are NOT any for the times I'm checking), I'll mention those.
With one exception (graduation gift for daughter), we've not "gifted" any points to someone when we weren't traveling with them. So far, no one's asked us, too and I'm glad. Hate to say no, but I would! Don't have enough points to share in that way.
Doubt I've helped you, any. But thought I should say more than "It depends!"