Make your town look awesome, rent farms, rent/sell plots, shop with building supplys and if you have repair feature do free repairs for town members. So don't just do one think sell everything you can.
Make your town insanely awesome and sell really expensive plots. (which is what I am doing with my towns)
I chose to build my town on a jungle island and built some nice apartments and condos onto it. By the time I finish the whole thing I will have over 100 rooms, each with an average value of around 4k, which will earn me 400k, plus a 100k penthouse. I know that these will sell because I've actually sold quite a few of them so far, some at a much higher price than I've expected.
BTW to make a poll you go to the bottom and click *poll creation* And i would say the best is selling plots. And making condos