Windows version code:
Increase White Marks: acquire a level two house and make the tenants punks. They will soon complain about a hedge. Drastically decrease their rent to get white marks. Raise their rent and repeat as desired. Either agree to their demands, replace them or make them have children to break the cycle.
DOS version codes:
Enter the following codes at the single player or network player selection screens, then hit [ENTER]. Correctly applied entries will not appear on screen. Successful completion is noted by a beep. Once in the game, press C. A + sign beside the date indicates that cheats are active.
ACTIONS674: enables all undesirable actions on the easy skill level.
BUILD909: [CTRL] builds instantly when placing houses.
CADETS552: enables police cadet bribes [ALT-P] and mob bribes [ALT-M].
COMPLAIN840: [ALT-C] turns complaints off.
ESTATES131: enables the limitless purchase of any estate.
FENCES673: enables the limitless building of fences.
GADGETS337: enables the construction of every gadget.
GANGSTER822: enables the limitless conversion of workers to gangsters.
HOUSES738: enables the limitless selection of any house.
LOANS039: enables the limitless borrowing of money from the bank.
MAP751: enables play on any map with any number of players.
MISSIONS824: [ALT-I] toggles missions on and off.
SPEED471: speeds up network games.
TEAMS418: enables team alteration in single player mode.
TENANTS127: enables the limitless selection of tenants.
WEAPONS473: enables purchase of any weapon for gangsters.
WORKER902: enables the limitless purchase of workers.