The title pretty much says it..... How do i rent dungeons such as aquila?
If you are a member, you can't: as long as you have a membership and meet the level requirements, you can go there as long as you keep the membership.
If you are a crowns player: when you jump on the sigils, a pop-up will appear and prompt you to either buy the zone permanently or rent it for x hours. Just click on the 'rent' option, and you're set. Unless something has changed recently, the Aquila dungeons are the only ones that can be rented.
I bought Aquila back when I was a crowns player and I remember seeing the option to rent, so I'm pretty sure that's how it still works.