"SpaceX’s Falcon 9 rocket is currently being offered at about $54m a launch. That is very competitive by today’s standards, but it would be substantially cheaper still if elements of the rocket could be recycled. The company says the first-stage represents almost three-quarters of the cost of a Falcon 9. Clearly, in carrying extra fuel and landing gear, you take a hit on the rocket’s performance – the maximum payload you can carry to orbit is cut by about 30% if you try to return the first-stage to the launch site, says Musk. But the imperative is clear." (Quoted from article)