First off, I am so sorry you are having to deal with this.

For you and your cat's safety I would not recommend applying diatomaceous earth indoors as it can cause harm if it is inhaled. 

I would first recommend identifying what type of roaches you are dealing with to target your management efforts before your move.

• Common small roaches in Maryland-
  • German cockroach (Blattella germanica): Adults have two dark "racing stripes" on the shield (pronotum) behind/over the head. Immatures will have two dark stripes running down the length of their body.
  • Brown-banded cockroach (Supella longipalpa): Adults do not have "racing stripes" but have faint V-shaped lighter bands on the wings.

You are welcome to send us clear, close up photos and we can do our best to help with identification. You can visit our University of Maryland Extension web page on cockroaches for photos and descriptions of the five most common roach species found in Maryland homes/buildings.

For management and control in the meantime, I would recommend a combination of sanitation, baiting, and monitoring.

• Sanitation: Reduce food sources by storing food in tightly sealed containers, rinsing cans and bottles before recycling/trashing, wrapping or containerizing edible garbage and removing it from the home frequently, and consistently cleaning crumbs and debris from all areas of the home.
• Vacuuming: Can be used to remove crumbs and debris as well as to remove roaches. It is recommended to use a vacuum with a HEPA filter to reduce airborne debris when vacuuming roaches.
• Baits: Commercially available baits come in pastes, gels, and granules. Most baits are slow-acting and may take a week or longer to show results. It is recommended to place baits near hiding spaces or areas where roaches have been seen searching for food (under appliances, along walls, etc.). Baits may not be equally effective for all roach species (e.g. brown-banded roaches are harder to control with baits). Be sure to read and follow all directions and safety precautions listed on the bait product. The most popular bait application method for home use is prefilled bait stations, small plastic units that contain an attractive food base along with an insecticide. Refillable bait stations are available in stores and can be refilled with bait granules or gel. The advantage of bait stations is that insecticides are confined to small areas within tamper-resistant containers rather than being dispersed widely, potentially reducing exposure to people and pets. We do not have a specific active ingredient to recommend. We would first recommend identifying the type of roaches you have.
• Sticky traps: Sticky traps can help with monitoring roach activity to identify hotspots and to evaluate if control measures are working. Most home and garden stores sell sticky traps- these traps are open at both ends and are lined inside with a sticky material.

If you have any further questions or need help with identification, please let us know.