My husband works there doing carry outs and inventory...and I've heard it many times. Store policy says THEY are NOT supposed to lay it flat when THEY load it into your car. Now, you can if you want to but because the foam inside is usually thicker on the edges of the box...it will usually break the screen. Which is why you'll see so many people using straps in the bed of their pickup to hold it upright. Because even if the straps are tight, the foam on the edges will still protect the TV better than if it was flat.
You shouldn't as you could very well shatter the screen if you hit a bump to hard.
I have hauled many in a suv/truck. They are packed very good if you are buying new.
Depends on size of TV and and size of vehicle. Measure backseat and Measure TV you want
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