All modification work can be done true UI :

Adding or removing perms/groups  .
Customize the permissions/groups .
Changeable Perm/Group Title , ImageUrl, Description, What Perm/Group they will get , Cost .

Flexible Economy :

Item-Based Economy: Use in-game items as the currency for purchases.
Plugin-Based Economy: Economics, ServerRewards, and CustomCurrency.

Commands : 

Chat Command : /buyperms – Opens UI (Changeable chat command in config).
Console Command : open_perms_ui – opens UI.
Console Command : remove_perm <player_id or all> <permission or group_ or title>  –  remove from player or from all players that specific perm/group/title.
Console Command : wipe_perms <player_id> or <all>  –  with this console command you wipe for that player , or for all players buyed perms/groups.

Perms :

“permbuy.buy” : required to open UI.
“permbuy.admin” : required to be able to add/remove ,modify perms/groups true UI .
“permbuy.bypasscost” : required for not taking any cost when you buying .

Lang File Supported – you can change all texts there !
Data file – you can see there who buyed what !

Example Config :
“Open UI Command”: “buyperms”,
“UI Title Text”: “Buy Permissions/Groups!”,
“Show Purchased Permissions in UI”: true,
“Cost Configuration”: {
“Economy Type [Item, Plugin]”: “Item”,
“Plugin Cost Type [CustomCurrency, Economics, ServerRewards]”: “CustomCurrency”,
“Item Shortname (if using Item-based)”: “scrap”,
“Item Skin ID (if using Item-based)”: 0,
“Item Display Name (if using Item-based)”: “”
},
“Available Perms/Groups”: [
{
“Perm/Group Title”: “God Mode”,
“Image URL”: “https://www.dropbox.com/scl/fi/18yy55g7bfcz8tj4yhnkr/5e2c4da074770.png?rlkey=24zmukgzu3rll382s6wpkbd65&st=e1bi9i7k&dl=1”,
“Description”: “Allows you to become truly invisible”,
“What Perm/Group”: “vanish.allow”,
“Cost Amount”: 100
},
{
“Perm/Group Title”: “Bronze VIP”,
“Image URL”: “https://www.dropbox.com/scl/fi/ir8e03hvw0wtv59ofbey1/bronze-badge.png?rlkey=9gq4axhg5swt92dgqar6jk97e&st=8rz8iqh9&dl=1”,
“Description”: “You will be Bronze VIP player!”,
“What Perm/Group”: “group_VIP”,
“Cost Amount”: 200
},