J.✰.
Figure out what is your 'broken' thing. Dad may try to fix it over the phone instead of driving over to your house. Maybe you need a tool that only HE has that way he HAS to come over. And he may arrive in his 'handy-man' work clothes. So consider that too, when deciding WHY he needs to come immediately over to your house. Granted, luckily your mom is there to say something like "Oh honey, you don't need to change into your work clothes. Just go in what you're already wearing."
Good point Joanna - lots of cars near your house might be a dead give-away. Maybe have them park mostly all on one side of your house instead of on both sides so it looks like a neighbor down the street is having the party - and so he doesn't see cars he recognizes, they need to park so that he doesn't drive BY them on the way to your house, but that they park on the other side of your house. Get what I'm saying?