I don't have roaches inside but see a dead one outside once in a great while. These are always American (large) roaches. So I keep roach baits in the house - Combat used to be the major manufacturer but now all I see is Raid brand. They come in two sizes - small (German) roaches or large. I have a hard time finding those for large roaches but those for small roaches are usually common.
Last time I needed a fresh supply I couldn't find the large roach size. A employee (owner I think) of the hardware store I see there most of the time said either size will work for either roach so I bought the small size.
What's been your experience? The big roaches can get through the smaller openings into the small baits to eat the poison?
TIA