9. Check your air conditioning
This one’s not rocket science, because there’s not much you can do to service your own air conditioner. But since your air conditioner is the only thing that separates your family vacation from a trip to hell, you want to make sure it’s working well. If it seems like it’s not blowing as cold as it should, have it checked out. The problem is probably a low refrigerant level, which is a fairly cheap fix. If there’s no cold air at all or the fan won’t come on, that could be an expensive one.