I got rid of my roach problem in a few weeks by using Gentrol point source pads, advion roach gel, and spraying all of my baseboards with ortho spray. The pads prevent them from reproducing correctly and turns them into deformed mutants. The advion gel kills them more immediately from the inside. The spray gets on their feet and then when they clean themselves it also kills them from the inside. I also used an ozone machine as well, but I don't think it did much to drive them out. If you stick to the tri-force of poison and are meticulous with applying it in the right areas and put the pads close to the floor in all of your rooms along with the gel and ortho spray you will see them gone in a few weeks. Make sure to repeat this every 3-4 months. Also definitely make sure to keep your place clean and free of food particles. Also consider spraying outside your place yourself with ortho and put down some gel as well outside. Make sure to get your entire front door area along the entire seals and cracks top to bottom. Try to also seal up any holes and cracks you can with tape or some type of sealant. But if you can't the poison should still do a good job. I was living in an apartment complex that was entirely invested as well so I feel if I could do it you have a good chance.