A very twisted but probably cheap Earth-Moon transfer:
- maglev train on "renewables" in tropics
- plane that burns surrounding oxygen
- ionocraft to reduce reaction mass to carry
- solar sail with standard chemical or maybe soon nuclear thrusters
you can use nitrogen outside of atmosphere, bonus points for expanding your sail with satellite debris - many-many revolutions with constant steering
- pretty neat if someone have already built railgun brake on the Moon so you can bring less fuel.