we had a flea infestation at our house a few years ago. We bought 3 flea bombs and let them off and left the house for the day with the wondow wide open. The fleas never ever came back.

As for the ants, GGRRRRRR we have the same problem, just get rid of one lot and a few days later another lot comes in! I am planning on getting the ant sand to put on their ant line outside the front door, hopefully that will stop them a bit longer.

I bought a pack of little round plastic things that the ant eat and then take back to the queen, they worked a treat in the spare room, I should get some more for the kitchen.