Lower availability in character creation
 

Is it possible to set it to like... 6? I'm doing pretty low power level campaign.

Open the editor (tools...show editor), create a new file, and save it in the default directory. Then, on the tools tab, find "Character creation mechanics", and use the "New (Copy)" button to make a copy of the character power level you want to replace (like established runner or street-level play).

The availability limit is about 2/3 of the way down in the list of settings there, so change that. Then, the second item in that list is called "Search sequence". Change that so that it's a lower number than the default (for example, on established runner, the default is 10, so change it to a 9).

Then, give your mechanic a new name, give it a unique Id, and then save it and save the file.

The "Test Now!" button doesn't work well for mechanics, so close the editor, and in the main HL window, go to the Develop menu. Make sure that "Enable Data File Debugging" at the top of that menu is turned on, and then choose "Quick-Reload Data Files". Now, when you create characters using whichever power level you made a copy of, you'll get the changed settings.

You'll also probably want to give your new mechanic a source so that you can turn it on and off.