does anybody know how/where to store The Liberator in GTA V story mode? I tried in Franklin's garage as well as Trevor's and neither worked. Thanks
No need to store it in the garage, you should be able to select special vehicles at some point and it should be listed.
Found in each protagonist's garage in single player in the Special Vehicles section. It, along with the Sovereign, were no longer available as of 8/5/2014 due to a glitch. Both vehicles returned to the garages after the San Andreas Flight School Update (XB360/PS3).
Special Vehicles are features in the Grand Theft Auto series, this article contains a list of all the special vehicles featured in Grand Theft Auto V.
I have no problem storing the Liberator in Franklin's mansion garage. It takes a little force but it will squeeze in. Just stop the vehicle before it's roof reaches the concrete beam in the garage ceiling. This will make backing out much easier. This is my experience using PS4 in story mode.