[bjnord]

"Is SpaceX going for 2nd stage reuse at all? That's going to be a lot harder"

Yes, they are (and yes, it will be): "SpaceX also continues to study the feasibility of returning and reusing the second stage of the Falcon 9, and Musk said he’s confident it can be done. The question is what “mass penalty” will have to be paid, primarily in terms of the fuel needed to slow the second stage down so that it can make a controlled descent back through Earth's atmosphere.

"Still, Musk believes the Falcon 9 will get to full reusability. In terms of the rocket’s overall cost, the first stage accounts for 60 percent, the upper stage 20 percent, the fairing 10 percent, and the remainder are costs associated with the launch itself (fuel costs are between $300,000 and $500,000), Musk said."

https://arstechnica.com/science/2018/05/spacexs-block-5-rock...