New unit less issue, old unit sure will get.
high floor less problem with roaches provided the building do pest control every 6 months or you can try spray the rubbish chute area every month with some ridsect/shieldtox

Roach bomb your unit. last time my unit always got the small crockroach come in. bomb every year also will find them inside every now and then. initially thought got nest inside behind the kidchen cabinets, etc... but usually they come from outside or hide behind the walls, etc... They usually come in via the pipes or cracks in the tap/tile area