Why a one-way trip, you ask? Well, there are two reasons, the first is that a huge part of the mission's expense is in bringing the crew safely back to Earth and the second is that leaving people on Mars could lead to a long term human colonization. NASA Ames Research Center director Simon Worden expects the plan to go into effect in the next two decades and so far NASA has donated $100,000 to the project and DARPA contributed another $1 million. Although just pennies in comparison what the final budget will be [HUGE] Worden hopes to convince others to invest.
Astronaut Buzz Aldrin also agrees with the plan:
"we can be well on our way to Mars by July 20, 2019" and believes in building a colony on Mars. He told Vanity Fair, "I'm convinced that sending people to Mars is so expensive that if you go once and bring the people back and then go again and bring the people back, we're eventually going to run out of money. But what if we send people the first time and they don't come back? What if they stay there?"