Hello,
I had an ant problem until quite recently (for a few month at least). The ants can all the way into the house and led their friends in as well (there were hundreds).
Killing them manually, vaccuming and hiding their scent trails with floor cleaner was not fun.
I eventually purchased the best ant killer, boric acid. I put it in front of the house and they licked it up, took it home to their ant colony and died!
I never saw any more ants again
(i pity the little guys but they were getting bad).
I will post pictures soon