My neighbour is 93 in a few weeks and has lived in the same home for nearly 90 years. She has had an issue with small ants each year and when we get older we stress more or many do. She is an anti chemical person and sure i looked up once and read about some not to bad stuff.

Its a really old two storey home with a crawl space only under the middle part of the home. The whole in the kitchen floor to go down there is so narrow it wont down through it again, did years ago and not impressed.

She is really clean there never leaves stuff out. Does have two cats and maybe the food attracts them.

If she would let me cut a larger whole in the floor id go into the crawl space and poke about. There has to be something going on down there approx one outside wall in the crawl space. They are tiny ants its winter and shes had this every year. I could buy her an Ardvark but not sure what the cats would think.