A simple trade command for non premium users :

Variables Needed :
Trade = 0
Trade User = 0

Command 1 :

Trigger : .trade

Language : BDScript 1

Trade Send Code :
$onlyIf[$getVar[Trade;$authorID]==0;Someone else is sending you a trade request with you type `.accept` or `.decline` to trade with someone else again]
$onlyIf[$getVar[Trade;$mention[1]]==0;The user is currently having a trade request with someone else]
$onlyIf[$mentioned[1]!=$authorID;You can't trade with yourself]
$title[Trade Sent]
$description[Your trade request was sent to <@$mentioned[1]> for him to accept your trade he needs to type `.accept`]
$color[ffff00]
$setVar[Trade;1;$mentioned[1]]
$setVar[Trade User;$username;$mentioned[1]]

Command 2 :

Trigger : .decline

Language : BDScript 1

Trade Decline Code :
$onlyIf[$getVar[Trade;$authorID]==1;You don't have any active trade requests yet]
$title[Trade Declined]
$description[You declined $getVar[Trade User;$authorID] Trade Request]
$color[0000ff]
$setVar[Trade;0;$authorID]

Command 3 :

Trigger : .accept

Trade Accept Code :
$onlyIf[$getVar[Trade;$authorID]==1;You currently have no active trade requests]
$title[$username and $getVar[Trade User;$authorID] trade]
$description[$username's offer :
🔴 Nothing

$getVar[Trade User;$authorID]'s offer :

🔴 Nothing]
$color[ffff00]

Sorry that I can't make the .trade add item/money command because that command depends on the variables on your app