I’m sure many who paint cars or apply vinyls on a regular basis have been annoyed by environmental effects disrupting their work. Sunset making your colors look off? Night making your colors not look at all? Glare from lights mounted on the ceiling of the Festival garage obscuring the pixel-perfect location you want to place your vinyl at? Even something as simple as colored walls can have an effect on how we see a given color applied to the car.
In order to get around all of these issues at the same time, I suggest a premade downloadable garage layout designed not to look good, but to make your work look accurate. In order to achieve this, the garage would need middle gray, completely featureless walls, floor and roof. Roughly matching 18% reflectance of visible light often used in photography for accurate color rendition, this gray would have Hue: 0.00, Saturation: 0.00 and Brightness 0.46. Then, to reduce glare and shadows, all lighting would need to be indirect/ambient/diffused.
Now, I think this may be partially achievable with manual garage customization (assuming the customizable garage will actually have uses other than being a display cabinet), but I’m mostly worried about the light sources, which is why I believe a premade, sterile painting environment like what I described would help.