The Slums of the Solar System Books 1-3 by Kate MacLeod

This box set collects the three novels in the Slums of the Solar System shared world: MITWA, THE MARS OF MALCONTENTS, and A WHOLE WORLD FOR EACH.

MITWA:

When a deadly plague ravaged the Earth refugees fled into space, crowding into any space station or lunar colony that would take them. Decades passed and the descendants of the survivors struggle to live in anything remotely spaceworthy.
Omesh, banished from his Earthly home, finds himself in Barnacle Town. A collection of salvage clinging to the hull of a space station in lunar orbit. Thousands of lives cling precariously to the hull, at the whim of the corporation that owns the station.
The station manager welcomes everyone. But then the CEO arrives, intent on scraping the hull of his craft clean. Omesh and his family, friends and neighbors? Not the corporation’s problem. 
With nowhere else to go, Omesh vows to fight for his new home. But physics? More merciless than any CEO.

THE MARS OF MALCONTENTS:

Valentina knows how to live in the community spread throughout the old mining caves under the Martian ice cap. A violent place in a forbidding climate, but home for her and her brother. Until she wakes from a coma to find her brother gone. Her father thinks her incapable of following them back to the equatorial cities. He underestimates her – her stubbornness, her courage and her inventiveness. But she underestimates the cold, airless surface of Mars. A journey from the polar ice cap to the Martian equator? Not enough to stop Valentina. Not with her brother on the line.

THE WHOLE WORLD FOR EACH:

After humankind fled Earth for space they discovered one inescapable truth. People die in space. And lots of dead people means lots of ghosts. April Nguyen earns a nice living getting rid of those ghosts. People all over the Solar System clamor for her aid. 
April's only problem? Never actually seeing a ghost. She pretends, she feigns, she completely convinces her clients, but she fears her inevitable exposure as a fraud. 
And then comes Hakim, the ultimate suspicious sceptic watching her every move. And yet April feels herself drawn to him. He knows a whole other world.
"The Whole World for Each", a story about belief and disbelief and how we jump between the two. Humankind escaped Earth, but not death and what comes after.