This console command sets the transparency of your target.
setactoralpha [alpha] Target Command
| Alpha | A number between 0 and 1 (e.g. 0.5). 0 being invisible, 1 being completely opaque. |
setactoralpha 0
The above command would make your target invisible.
setactoralpha 1
The above command would make your target completely opaque.
setactoralpha 0.9
The above command would make your target slightly transparent.