Bulldoze houses/fountains/statues (trick)
Within the city, there is a concentric circle from center outwards. Within this circle, towers (big office buildings) will appear. Fountains and statues build by the city account for 0 (zero) inhabitants. You can remove them, so a tower will appear. Small houses do have inhaitants, but generally up to 35 (7 or 14 for smaller houses). It's better to have a building appearthere having 100+ inhabitants, then let the house stay there.