We actually did a previous post on this game and if you are careful enough to read it, you will also find a cheat guide I revealed there somewhere. I try to make it a point that I only add more residential lots only when I have maxed all previous residential buildings. So that way, I earn more simoleons from taxes.
I will be posting my very own video soon so keep watch of it. I've read a few trick to play it offline and advance the time to quickly get the needed materials. I haven't tried it yet but I might give it a shot today.
Ill report the results here soon so be sure to bookmark our page for this crazy trick.