I've been playing my current save for months now... I started with one sim. Then he met his partner at uni and had 8 kids.
He started in a house but immediately went to uni to find his partner and stayed in a dorm rather than a private house on campus. I prefer the dorm life or sorority life, etc. I was not shy about using money cheats as I didn't want money to stress me out when I knew I was becoming attached to the sims and would be playing the save for a while.
There are a few buildings that I liked to add to the town once they got back from uni and started their family. The Butterfly Escapade from Bridgeport, and the greenhouse from the store, for instance.
Then I populated the town just a little bit more with some sims of my own creation, then went on to even transplant some of my favorite sims from Bridgeport into Starlight Shores.
I chose one kid to be heir and she is going to have children.
A lot of people move out their non-heir children, but I'm too attached. I'm keeping them all unless there are extenuating circumstances in the future. (Example: My computer saying 'no' to how many sims I have.) :D