I mean- You could look at your payment option logs, such as a credit card. However, I feel as if this would be cool to have. One thing to worry about is the fact that this may be extremely hard to program, if it's on the server. If it's possible, I'd love to see it implemented so +1
Usually, If you are using Paypal to purchase a rank (Which so far that's the only way to get a rank on here). They send you a receipt to the email you used. In that receipt, there is a timestamp on when the rank was purchased and all the information you need about purchasing the rank. All you have to do is search up Paypal in your email search bar and all purchases via the website (Mostly MC sites) will show up with the receipts.
But I do like the idea of a way of an easier way to search up your purchase history on the site. Like in the store itself.
To my knowledge, most people who have had purchased a rank, had a parent or friend assist them with it. For this reason, the player may not be able to have access to the statement unless: [1] They ask their parent for access and/or to see it. [2] They purchased a rank using their own money, and have access to their own statement.
I think this would be not a necessary thing to add, but definitely, something that would make it easier to view when you got a rank.
If we denied everything that isn't "necessary" a lot of things on PartyZone wouldn't exist.
Agreeing with what's been said above, it may be difficult to implement in the network.
However, if it's possible I would enjoy seeing this in future updates.