Legit sites do provide mining address and payment proof to the persons who receive payment.
Tell me one such legit site. Hashnest, Genesis Mining or anyone? All it needs to show the mining address and sold hash power in real time. But none. Not a single cloud mining website is showing this.
there were a couple of them that was actually legit with mining equipment and hashpower to really mine bitcoin but these days all of them (that i was familiar with) are now closed and the rest are scams
you can find out about them here:
https://bitcointalk.org/index.php?topic=878387.0