I lived with friends,where we couldn't get rid of the cockroaches...
Now I moved into a roach-free home ( I know for sure,because I inspected everything carefully before moving in) only to find out ( oh horror) that some roaches have travelled with me inside my moving boxes!
I haven't seen that many yet but I'm sure they will lay eggs soon... which is the best way to get rid of them for good?

I know your problem so well. My dad and I went to the 99 cents store and found this power substance called ECHOLS by No Bugs Goodbye Roaches! 99% Boric acid Roach Killer and it works. What it does is you put it like a ring round your house side by side and the roaches will pick it up go to their queen and give it to her as food she will eat it and die and so will they and their babies. Here is the manufacture: Kittrich Corporation/Athena Divistion La Mirada, CA 90638