The Martian Race by Gregory Benford
The premise of the story is that problems have derailed plans for a government program to go to Mars. A $30 billion prize has been offered to the first private mission to Mars. (To win the prize, the private mission must fulfill specified science work on Mars and return to Earth.) Governments have figured that as large as the $30 billion prize is, it will be cheaper than all the various efforts to achieve a mission by the existing government agencies. (Also, they've figured that the governments and politicians won't get the blame for any disasters that strike a private mission.)
Two major competitors become involved in the effort to gain the prize. One team is sponsored by an American billionaire, the other by a joint Chinese-European venture. We are mostly made familiar with the efforts of the American effort.
In order to make the private mission financially viable, two major accommodations are used. First, they get money from other companies for advertising right, special news access or other special rights. Second, the mission is organized with slimmer safety margins and unconventional approaches. One of the unconventional approaches is a separately sent return vehicle which requires production of fuel on Mars for the journey home. One of the reduced safety margins is the cancellation of a backup that turns out to be a nearly fatal decision.
We get an extensive look at the planning, debates, solutions to dilemmas, preparations and training for the mission.
The plot is full of the dynamics of getting the mission together, the competition between the two missions, scientific work, the crisis of the disabled return ship, and the search for signs of life. And, yes, we get to know the people.
Another fascinating part of the book is a look at a kind of habitat and life form that might be possible on Mars.
Some readers may find the corporate approach and dangerous risk-taking to be uncomfortably too familiar to the Scrooge-like greed machines that flourish in today's economy. These readers may find a chilling side to the story.