missions to examine space craft that have been in space/moon for decades could be quite profitable, as these will provide engineering feedback as to what parts are still operable and how things failed and what might be done to effect repairs, as this is how aviation reached the level of reliability that it enjoys today, but with space bieng even less forgiving. We are getting lots of data about operations in LEO, and some from Mars, but the moon is tough, too much dust,no atmosphere, not enough gravity, and very wide temperiture/radiation swings that last for weeks,and actualy more difficult to build for than mars or leo.