They are special cars that Turn10 gives out. They are unobtainable in game (you can only get it from the auction house or from competitions Turn10 hosts).
yes
You can't
There are about 400 cars in forza but you can get a extra 90 by dlc
the vinals you se on the cars are made out of micilanious shapes found on the "paint your car" section of forza.
500 cars
1300
All cars can be turned into a non front drive car.
To sell cars in forza horizon one must first have a properly register account. One must then enter as many details about the cars they are trying to sell as possible.
purple is my favorite number in alphabet
More cars and tracks probably
Forza 3 has 1 player online, or 2 player split screen. In split screen you can have computer controlled cars racing too. This is one reason I like Forza games, as games like NFS Shift, Grid, Pure, Dirt, and Dirt 2 don't have split screen. Trust me, I have Forza 3. =D
no