i did a complete clean when i arrived first and sprayed any i found ruthlessly. After that complete disinfection/clean any time there were guests with food over. NO food is left anywhere except in the fridge. I also dislike cockroaches a lot 

Yes complete clean, with 'Raid' and especially in Summer, throw garbage every day out, also clean plates, etc. 

To catch them, the famous beer trap. Full a glass with beer and put it against the wall of the bathroom. 

When I first moved into Beijing, I was placed into a complete cockroach motel by my esteemed training center, and I was pretty much stuck there until I could find another place. Training centers in China take really great care of you like that. Roaches in the kitchen, the bathroom, the living room, and, yes, my room. I managed to get them out of my room by scrubbing everything down like mad. Also, you know how some earth-based religions keep evil spirits away from them by drawing a circle around their homes with a magic potion? I did that with bleach. I poured bleach around the premise of my room once every week. Eventually, the roaches were in the kitchen, the living room, the bathroom, but not my room, so that made me less miserable.

Now that I've moved into a roach-free apartment, I keep it clean. You can slack off cleaning somewhat in your home country--but I have no illusion that roaches are never far away from my apartment, and will happily scuttle inside if there is enough for them to eat. I take out the trash, wipe down surfaces, and do the dishes like it's my religion. And I never leave food out...little demons will go straight for that. I also have a can of spray ready for the first one to come in.

I swear to God, I didn't even click twice!

invite me over to your apartment and we could have insane crazy sex all night. they will leave because of the vibrations. if it does work the 1st night than we could try a few more nights maybe even a month is we have too..

(sorry i'm in a dry spell)

There are some decent poisons around.  I've used one that you spray around and leave the flat for 30+ minutes and then you come back and everything should be dead.  But you say you sometimes catch them sneaking in through the bathroom?  Is that a whole in the wall because you're in an old building or something?  Sounds to me like you need to 

1.  Plug up all holes where things can get in

2.  If they're coming in through the drainage get covers for everything

3.  Unleash the death spray

4.  Thoroughly clean everything.  Use excessive bleach, leave no stone unturned, and destroy/chuck-out anything you don't like the look of.

Errrm assuming step 4 doesn't get you in trouble with the land lord/lady.

If it is an infestation then I don't think roach bombs, Raid, or excessive use of bleach to thoroughly clean the apt will help.  But I would say try every method/suggestion given and then look for 9, 10, 100 more lol.  If you're not under contract for an extended period of time and/or not financial strapped, I would also keep relocating to another apt under consideration. 

My flat cockroach runs free. I feel sorry for almost crushing it.

At my place, they come out of the so called floor Chinese toilet, so before going to bed, I pour the local version of Clorox down the drain, and I seldom see a roach now days.  I do also keep a can of RAID handy, but has lasted months now.

I never cook at home, so the food here is minimal. Never really have problems with roaches. In Guilin, my big problems were spiders and centipedes. Those things get into everything.

Word to the wise: In southern China, do NOT live on a first floor!!!!

What is a flat cockroach, and why does it need to be free?

I call the exterminator and have him exterminate all the cockroaches.

Thanks for all the tips everyone!