Outdoor fleas and ticks travel indoors and vice-versa. Because of this, it is important that any flea & tick treatment address both indoor and outdoor regions. If it does not, you may find yourself in a constant battle against these bugs.
Prior to treatment, it is important to expose insulated areas. This is due to the nature of fleas & ticks. They like to nest in these safe, secure nooks-and-crannies. It is also important to rake and mow your lawn for this same reason. Doing so ensures treatment chemicals penetrate the covered areas fleas and ticks inhabit.