Make sure you do not use balsamic vinegar!
I used normal white vinegar in a spray and it worked for a while. Then just as we were going out shopping we noticed a few had reappeared. So as I was busy for a minute, my flat mate sprayed what I thought was white vinegar, but it was balsamic! We came back just 40 minutes later and there were hundreds of ants as it is a sweet vinegar! Some were even flying ants! We had also left a kitchen window open and there was a bird flying around in the kitchen. It was an awful experience. It was like a nightmare, how the brid ants and flying ants all happened in that short space of time!