The Actor Trailer Is a Prop introduced and unlocked when your Sims Reach Level 10 of the Film career the actor branch.Sims Can WooHoo in the trailer (but may get caught by the paparazzi) and Sleep in the trailer but it is a rabbit hole like the Treehouse and other commercial buildings on The Sims.
The Actor Trailer is available to place on your home lot. It is like the gifts you get from work and other people. It is usually placed in the Family Inventory.