We have 1-2 a month, almost always in the kitchen.
For outside, I get
this or whatever is available at Lowes. I spray around the entire house, with special attention to doorway thresholds. I think that's what keeps them down the most.
We also use standard bait traps under the sink, fridge, stove, etc. and put
gel behind the switchplates and outlets to get at those in the walls.
I haven't had a lot of luck with boric acid, I think mostly because it's difficult to get it applied lightly enough. Gets too clumpy.
We were also advised to try spreading moth balls in the crawlspace under the house, but those are toxic; naphthalene does not break down in the environment and seeps into the groundwater. I'd rather live with the roaches!