Size of problem
One thing I've often pondered, and never seen the maths on yet, but Mars is only about half the size of Earth. To launch anything significant into orbit from Earth needs a fairly BFR (Big Rocket), and I would assume that launching anything from Mars would need a rocket maybe a quarter the size if my fag-packet calculations are right. Assuming it's a Sputnik size launch from Mars, a rocket quarter the size/power of an Earth equivalent is still a multi-stage, 30-tonne rocket about 10m high - that in itself needs to be landed on Mars. I'm guessing my numbers must be way off, but right now I can't see any stories detailing what those engineering requirements might be.
The whole manned mission to Mars is an even larger problem.