help with one specific document tube puzzle

[Pebbles]

obviously spoilers!

I am stuck on the last document tube: modern design proposal. I cannot understand what the hint "any hidden costs?" mean for the life of me. if anyone knows how to solve this puzzle, please let me know!

[herbert]

it is referring to something being visually hidden in the blueprint
no it doesn't really make sense, but your takeaway should just be the word 'hidden'

[Pebbles]

ok so I turned the page so North points up, and I can see the number "761" in the rooms' shapes, but apparently that's not the correct answer either. please help lol I am struggling

[Ravage]

I believe this is bugged, I had 761 in two of my saves. Try 714.

[Pebbles]

714 worked! thank you so much for your help!

[Mushu_senjak]

because you need to look to the wall not the room ^^ it's realy confusing (but I supossed it's the point)

[NishYou]

Originally posted by Mushu_senjak:

because you need to look to the wall not the room ^^ it's realy confusing (but I supossed it's the point)

I was stuck without a map for that floor for the longest during my playthrough coz of this simple reason, I was too focused on the empty/white space...

[Flint Webber]

Originally posted by Ravage:

I believe this is bugged, I had 761 in two of my saves. Try 714.

If it matters at all...

it's not a bug.
we all see 761 as we see the spaces of the empty rooms.

that's wrong it seems.

try something else inside...

Try the walls

[kahshmick]

Hrm, kinda strange to have a red herring answer that's adjacent to the actual intended one. I wish they could have added an extra wall to invalidate the incorrect "761" that seemed obvious to me.

[sobrien]

I actually saw the number instantly. Im surprised this was a hard one for people. I thought it was easy compared to the other ones which i found hard. I think its kinda like an optical illusion.

[genechtagazoink]

worst puzzle yet. :( let's see what follows...

[nexen]

Couldn't solve it, saw 761 too. But the worst problem with this was that all other puzzles are architectural while this one is "magical" one in architectural document which is nonsense.
I even though that maybe the answer is "YES" (4E5, 294 e.t.c)

Lost about 4 hours on this one till gave up

[zunaid.h]

https://ibb.co/cm7DNMQ

how exactly are you guys missing the painfully obvious 714? worst puzzle? magical? seriously?