You can put your unique behind a teleporter and restrict teleportation by level. Use an instanced, non-party based map, if you want to block reverse scrolls too.
The below example was extracted from a 110cap server. This is the Roc teleport, that has been set to max lv102 with D11.
If you do not have any additional parameters, you should put the 1st number into Restrict1 column, following by Data1_1 and Data1_2.
Code:
Restrict3 Data3_1 Data3_2 Restrict4
1 80 102 6
Usually the second number is set to 999 followed by 2, maybe this is for unlimited max level. Simply check the samples in RefTeleLink.