I tends to incorporate random scenarios in every household:
Career, Household, Pregnancy, Friends, Economics, Crime, Family, Romance, Enemeis and Death are the scenarios and each has six variations which I roll every 10 sim Days.

For example, Household one:
1,3,5) Upgrade
2,4,7) Renovate
6) Romeo/Juliette (Have two hating families Children fall in love)
8) Move to new house
9 ) Disaster (e.g set items on fire)
and finally 10) Lose everything

But one chance of the household roll, where a sim lose Everything, but Im not sure how simulate this or what to take in consideration, like family, funds and career. It feel like it would be a pain to buldoze every objects everytime I ge this roll.

I'd play it as rags to riches. Move the sim into a tent, then have them work their way back to where they were financially. To keep things interesting, you could roll new wants, have sim max out different skills, ect...

I frequently do "homeless, penniless teenager" runs. They can usually earn enough fishing on the first day to get a grill & tent.

Edit: Didn't realize this was the Sims 3 subforum. Never tried it there. Sounds like something to do..

With Nraas Master Controller and modules, you can create basically any scenario. Force move Sim to empty lot, delete his money, give him ragged clothes...

Then send them over to the business office and have them take a high risk loan to be able to afford food and an apartment (which takes the money module for Story Progression).