How to get rid of DLC Cars in NFS UNBOUND

Hi,

I bought the NFS Unbound Ultimate Collection on Steam (PC). I don't want the DLC cars in my garage right away, because getting the best cars for free kills the progression for me.

I already disabled all car-related DLCs in Steam, but the cars are still in my garage. Is there a way to remove them from my account or save game? Alternatively, could I sell them without receiving any in-game money?

EA ID: Tonicwave

Thanks!