a small dish or sprinkling of boric acid will rid your rooms of most crawling insects including roaches and large water bugs.
I just found that my floor cleaner “Fabuloso” will make those large water bugs (look like roaches on steroids to me) turn belly up.
The original Palmolive green liquid soap will kill fleas and ticks when used as a dog wash.
If fleas get in your carpet or furniture, put a small dish of some flea killer under a focused lamp light at night with the other lights off. My aunt used to use black walnut juice extract for the killer.
Actually a bowl of soapy water under the lamp is just as effective.