Bedbugs invaded my apartment after a new tenant moved in above fall 2020. Infestations were discovered in apartments above and next to me in the summer and fall of 2021 but not sprayed until then.

I captured over 300 bed bugs and documented them to the landlord, who had to get exterminators to eliminate them. They sprayed the apartment 11 times from 2021 to early 2022, but nothing reduced the numbers until they attacked the source infestations.

What worked:
Buying white box spring and mattress covers that bugs cannot get through and make them easy to see. Steaming and vacuuming the bed.

Putting glass and plastic traps on the floor under the bed legs. Bugs can't climb (some/all?) smooth, vertical metal, plastic and glass surfaces. Test for yourself. Large numbers of bugs could fill the traps so they have to be checked.

Tucking in bedding so that covers and sheets never slide onto the floor during the night.

Vacuuming floors every day to pick up bugs in the carpet or hidden under the baseboards.

Sealing pipes, lights, electrical plugs and switches with clear tape so the bugs cannot enter that way. I found two dead bugs trapped in a hallway light and then two more crawled out while applying the tape.

Completely sealing the vent above the stove after several crawled down, followed by more that were trapped in the clear plastic.

Sealing the bathroom vent with clear plastic packing tape around all edges of the wall, which bugs cannot climb, then sealing the fan cover onto the wall on all sides except the top so air could still escape. Every surface inside the cover and outside had smooth tape.

Some appeared on the floor near the front door into the common hallway, so I covered the first 60 cm / 2 feet of floor in bleach. This seemed to kill smaller bugs but a few larger ones made it through alive. The exterminator said they follow the smell of each other.

My freezer is -20 C. I put every bug in there for at least 2 hours, in a plastic bag, and none came back to life after they were removed and thawed.

Almost everything I have was put in either clear plastic bags or dozens of 60L clear plastic storage bins. I only found one bug in a clear bin that was right under a fire sensor I could not cover. It appeared to have crawled inside through the sideways U shaped top seals on the ends and died.

The plastic traps on the bed were in this form:
TTT Window
TDT
TDT Put these letters in 3 rows with the TTT at the top and window to the right of TTT in your mind.

The darkest traps labeled D had most of the bugs I found in the bedroom (~20 total), which led me to think they avoided light even though I slept head near the window where they would smell CO2. So, I started leaving all the lights on every day. I also turned down the heat but don't know if either helped.

Before I knew they were bed bugs, I killed about 12 in the bathroom over 3 months. Most would burst in a strange gray cloud.

Secure your bed, clothing and furniture. Then it is easier to deal with the stress and sleep in comfort. If you have to move, everything in plastic is safe and can be checked at the new home.

If it is really bad, make sure you and movers have covers on your feet. The first exterminator tracked them back to his house because he didn't cover his feet, but the government inspector always wore them when inspecting the building.