http://games.chruker.dk/eve_online/basic_skills.php

Below -2 = not in 1.0 systems
Below -2.5 = not in 0.9 systems
Below -3 = not in 0.8 systems
Below -3.5 = not in 0.7 systems
Below -4 = not in 0.6 systems
Below -4.5 = not in 0.5 systems

• Class 1 = Hideaway or Drone Cluster (easiest)
• Class 2 = Burrow or Drone Collection
• Class 3 = Refuge or Drone Assembly
• Class 4 = Den or Drone Gathering
• Class 5 = Yard or Drone Surveillance
• Class 6 = Rally Point or Drone Menagerie
• Class 7 = Port or Drone Herd
• Class 8 = Hub or Drone Squad
• Class 9 = Haven or Drone Patrol
• Class 10 = Sanctum or Drone Horde (hardest)

6/10* (Faction) Rally Point
7/10* (Faction) Port
8/10* (Faction) Hub
9/10 * (Faction) Hub
10/10* (Faction) Sanctum, Heaven