If you want to start a household with more than one person and want more than just $20k to start out, create each Sim as a separate family, then move one of them into a house and build a nice room. Now move one of the other Sims in next door and give them only a phone. Now have the two Sims develop a relationship and move in together. You can repeat this over and over and end up with a household of eight beginning with $160k.