Mindey, 
Astelliard
Billiard with asteroids: apply trajectory intelligence and domino effect to move large asteroids through a sequence of small ones.
There are so many asteroids. To move a large asteroid, like Cruithne to Mars, you don't have to do it directly. Small asteroids could push larger asteroids slightly to collide with even larger ones, until a larger one is cought by a gravity well.
Rather than investing $ to lifting more fuel, it could be invested into getting more information -- surveying the surfaces, masses, spins, etc. of asteroids to make precision collisions.
Inspired by [asteroid to mars] idea.
Credits: Inyuki of HalfBakery.
+[企画]
NASA: Dart mission
Asteroid impactor mission - may have relevant people to talk to. Wikipedia link
これは、初期エネルギー量が少ない惑星を動かす最も現実的な方法の1つかもしれません。太陽系全体の小天体の軌道をマッピングする必要があります。
This may be among the most realistic ways to move planets with small initial amounts of energy. Just have to map the trajectories of small bodies across the solar system.