Sedate the man and search his person
From Create Your Own Story
You wet your cloth with ether and sneak up behind him. As the man finishes relieving himself, you grab his torso and cover his nose and mouth with the cloth. He struggles a bit, then drifts off to sleep. You gently lower his head onto the ground. Searching his pockets, you find his car keys and a paper invitation.
You put the invitation in your pocket and drag the man’s body over to his car. You unlock his car and dump his sleeping body into the back seat. You throw the set of keys onto his body and close the car door.