Board Thread:Tapped Out Help/@comment-10662082-20130610050852/@comment-26143371-20161203142437

Does developing the Heights ever start giving you cash? No, not really. There are only a few minor things that give Cash (list might not be exhaustive):
 * Ziff Mansion has an income.
 * Billionaire Haven comes with Paris Texan, giving you an additional character with a regular set of jobs.

If you want to maximize your Cash income, it's best to not send your characters on Springfield Heights jobs, but instead assign them their "normal" jobs that yield money.