I think apartments needs maintenance and it's hard to communicate to the landlord there is a problem or fix or find someone to fix it. The mold is very common. The mold is very easy to remove when it's small but it becomes exponentially bigger growing. Go on Amazon search for anti-mold cleaning product and a spatula. When you see a mold 1cm large get on a chair spray and scrape. It will take 5 minute. If you wait 3 months thinking you should tell the landlord and then the landlord will call someone then the mold will have become 100 square cm, it will be a 100 minutes to clean.

The roaches too if they are in your kitchen call a exterminator. Don't leave food out at night, clean all crumbs.

If you don't take care of those things even in a a new building they will appear on their own after 2 years.