In defense of secondhand space stations: https://www.wired.com/story/the-plan-to-turn-scrapped-rockets-into-space-stations/

Every commercial rocket brings its upper stage right to the cusp of orbital velocity. Then it burns up on a fall back to Earth.

@Nanoracks has a better idea. What if those old boosters were converted into space stations?

Next year, it will demo critical tech to make it happen.

NASA has wanted to convert old rockets into space stations for decades, but was stymied by technological challenges and DC politics.

In the late 80s, NIST had advanced plans to convert the external tanks of the space shuttle into orbital warehouses.

The program to convert shuttle tanks into space stations made a lot of progress in the 80s. Companies were formed. Deals were made. It seemed like a sure thing.

Here are astronauts simulating a tank ingress at Marshall in the late 80s to show how it would work.

The plan went all the way to the White House before it was shutdown as a 'threat' to the ISS.

One of its architects calls the failure to put the external tank to use a tragedy of NASA's shuttle program.

So much usable material wasted at the cost of billions of dollars.

The idea didn't totally die. In the late 90s, Hilton Hotels floated an idea for "Space Islands" made from old shuttle boosters. No idea where it came from or what happened to the plan.

http://news.bbc.co.uk/2/hi/science/nature/293366.stm

A more serious plan cropped up in 2013. NASA examined the possibility of using a tank from SLS as a deep space habitat around the moon or Mars.

It was called Skylab II and a fullscale mockup was built at Marshall. This, too, withered on the vine.

Theres a lot of institutional inertia stacked against this idea. But commercial operators might finally be able to make it happen as demand grows for (un)crewed orbital platforms in LEO and deep space.

The future of exploration will definitely involve salvage.