Not that I condone going against your lease agreement, but I understand your dilema, and it's good you will be looking for a better place that will allow them.

Have you considered moving the rack into a closet, or portion of your home that is more easily concealable? What are the dimensions of the rack? Tall and skinny? Wide? Can you put a tapestry over the entire rack and use the top of the rack as a shelf/TV stand/etc?

Our snakes get very little light, the window is nearly blacked out, and we have our hatchlings in opaque blue tubs until they hit about 500g, then they get moved to a larger clear tub - they eat better for us in an opaque tub. Even with close to no light for the adults, they still seem to know when it's night time, because they start getting more active and looking for food.

The very fact that you have a weird looking rack of tubs that say things like 'winter hats' is suspicious. I'd use a tapestry/blanket to cover the entire rack (safely of course, being mindful of heating/wires), and find a better place to put the entire rack so it isn't so much of an undertaking to get them covered if the landlord comes over. I know they don't make much noise either, but if your landlord is ever in the room where they are at, consider playing some medium volume music, in the event that a snake decides to poop, or push around a water bowl.