The costs of Spacex's BFR

Since writing my two pieces on SpaceX's BFR (SpaceX, Mars, and genius and A ticket with SpaceX for $2000) I've done some more research and have come up with different cost estimates.  Obviously only SpaceX has accurate costings, and they're not telling us, but some enthusiasts at The Space Review have made convincing though contradictory guesses.

There were two articles which were germane: Estimating the cost of BFR (by Sam Dinkin) and SpaceX prepares to eat its young  (by Dick Eagleson, with insightful comments by Eagleson & "TheRadicalModerate") You have to dig through nearly 370 comments in the latter article to get to the estimates, but I dug.  I might still have missed stuff, though.

So here are the three estimates of costs:

I'd be the first to say that these "data" are very rough and ready.  And the calculations are complicated by the many uses that the BFR and the BFS will be put to.  The BFR will be used a lot as the booster for cargo launches of SpaceX's Starlink global internet satellite network, as well as for launching customer satellites.  On the other hand, the BFS will have far fewer uses (space tourism, servicing the ISS, setting up the moon base) until point-to-point spaceflights start.  Because the trip between Mars and Earth is only feasible for a couple of months every two years, if the BFS is used exclusively on the Mars/Earth run it will be used only for 12 round trips, because in 24 years it will assuredly be obsolete.  But note that even with these restrictions, it's still much cheaper than SpaceX's Falcon 9 launches.  So Musk's idea of using the BFR as a "workhorse" for all its operations makes economic sense.  And the cargo version of the upper stage (the BFCS?) will have a lower capital cost than the BFS and will be much more frequently used--it'll be much cheaper than the estimates in the table. 

Is Musk right that the BFR and BFS could actually be used for 1000 launches as opposed to more conservative estimates of 100?  This is key: if the capital cost of the BFR can be spread over many launches, its cost per launch will be very low.  I'm inclined to believe he's done his homework, so probably yes.  But even if it's only used for 100 flights, the cost/kg to LEO only rises to $59, and the cost/kg to Mars to $178.  Even limited re-usability drastically cuts the cost of space.

Will there be enough money to build the BFR and BFS from SpaceX's own funds?  Profit per launch is perhaps $45 million ($60 mill fee less $15 mill costs).  SpaceX will be doing 30 launches next year.  Some will be on re-used Falcon 9s, and will be sold for less.  But assuming an average profit per launch of $30 million, that will cover the construction costs of three BFRs and BFSs each by the end of 2018, even using Dinkin's costings.  And, once they start using them for regular launches of satellites and for missions to the ISS, their profit per launch will go up.

Before SpaceX came along it cost $22,000 per kg to lift an object or a person into LEO (low earth orbit)   If the BFR & BFS work, assuming a 75% SpaceX profit margin, Musk will have cut the cost of launching 1 kg to orbit by 200 times. 

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P.S.:  How much will media organisations pay to send someone on the first colonist ships to Mars?  A broadcast of the first steps by mankind on Mars will likely have the largest global audience ever.  Will that be a way to cover costs?