Supply Ship Smash and Grab

Supply ships en route established alien base may offer an extremely easy way to earn both elerium and money. Letting the right alien base live, rather then storming it, will result in a steady elerium supply ranging from 150 to 900 elerium/month, and aome money.

Race considerations

Naturally you want the weakest race around, which is Floaters. Sectoids are decent choice in early game, but later on their commanders are utilizing mind control which spoils the fun. Snakemen seem to have very good reactions. The other races are disqualified - Muttons are far too tough, not to mention Ethereals.

Terrain considerations

The best choices are flat and level terrain:desert deserts and arctic terrain. Farms are acceptable, though you'll have to deal with the barns. Jungles, forests and mountains are to be avoided.