The lights are on
We've heard from some readers that there are some issues with Grand Theft Auto V's garages. Apparently they have the occasional tendency to eat cars that players have upgraded. Rockstar has heard your laments and has born witness to the gnashing of your teeth.
The error typically presents after upgrading a car and then completing a mission. The company has acknowledged the glitch on its support site, but as of now has no workaround or fix to recover the missing vehicles.
Furthermore, Rockstar suggests that the problem may emerge after driving another character's personal vehicle (each of the three has them). A fix is currently being explored.
Additionally, it's important to recognize that safe house garages aren't magical. If you save a car in one, it won't likely show up in another.
You can subscribe to the support thread for information as it develops by signing into Rockstar's website with your Social Club ID.
Our TakeWith a game as big as Grand Theft Auto V, there were bound to be some glitches. Just ask the citizens of Fallout 3's Megaton how that stuff goes.
I hope this gets patched up quickly for those playing, but until then, be careful. Don't drive personal vehicles for other characters if you don't have to. It would be a shame if your sweet, tricked out ride disappeared.