If you want to do quick calculation, use this: https://ffbans.org/tools/G1CCalc
Then (if you logged in) go there to copy purchase history: https://www.gamersfirst.com/marketplace/ingame/purchase_history.php?gameID=20
Copy it into tool on FFBans.org (second one) and click calculate.
Tada, you have total G1C spent + total US$ spent on one account.
In my case it was 82,962 G1C which roughly translate according to site to 1,037,03 US$.
Ouch. I could buy new PC for that money.