Improvement costs, as estimated in this section, shall be defined to include material, construction and installation costs of grading, pavement, surveyors' monuments, drainage structures, storm sewers, sanitary sewers and other means of sewage disposal, water mains, fire-protection features, streets, gutters, curbs, culverts, sidewalks, streetlighting, shade trees, parking areas, landscaping, street signs, erosion control and sedimentation control devices, public improvements of open space and other on-tract and off-tract improvements. Residential private site work improvement costs as estimated in this section shall be defined to include material, construction and installation costs of driveways, curbing, walkways, water distribution facilities, sanitary sewage facilities, storm drainage facilities, finished grades of site work and landscaping.