This is a particularly disgusting variation of the Rags to Riches challenge. Basically, your sim will practically live out of the Dumpster on their lot.
-Create a Sim, male or female, YA or older, with the following traits: Slob, Kleptomaniac, Lucky, mooch, and frugal. (If you have Supernatural installed, replace the Kleptomaniac trait with Gatherer)
-Place said sim on an empty lot with only a Dumpster added. You can add other items essential for survival (such as a tent or BBQ) but the Dumpster is Absolutely essential.
-Your sim will have to get everything they need from either dumpster diving (either their personal dumpster or around town), Rummaging through garbage, or, if you have Ambitions installed, salvaging objects from the junkyard. They are not permitted to buy anything other than food. They can sell the stuff they find in the trash or have stolen, though.
-Your sim is also not permitted to get any job except a part-time job. To make money in other ways, you can invest in real estate, sell things the sim has made such as paintings, or marry a wealthy sim who CAN get a job.
-You can build a house for your sim or move into a pre-built house, but not until your sim has earned enough money to do so. They can't start off in a house. Also, any/all subsequent homes must come with a dumpster to dive in.
-When this sim has managed to collect 1,000,000 simoleans cash, the challenge is complete.