You'll need to launch more mass to get there but the technology isn't really any more complicated. It's also a more hospitable environment (reasonable gravity, day/night cycle, some atmosphere, water, etc.)
You'll need to sustain the astronauts for much longer and they'll be subject to a lot more radiation. That's not exactly easy.
It's a significant feat to even get a robot safely to Mars. We've never gotten one back to earth. I think you are underestimating the complexity.