Any house, no matter how well built or otherwise, will fall into disrepair in no time if regular upkeep is not performed. How many other HH homes are falling apart?
In 8 years? I can’t imagine a house in 8 years getting so bad that mildew and mold causes skin rashes. Even if NO maintenance were done.
Now the cockroaches have NOTHING to do with how they were built. That’s just people not caring about extermination.