ServerSign Command Shop?

I am currently creating a survival server for only me and my friends to play.
I wanted to make the server more fun than just the plain survival by allowing them to buy commands ( not for advantages ) to make it more unique.
I found a plugin called 'ServerSign' where you can apply commands to signs; and on the website it says "Implement if/else and return statements in commands on ServerSigns" so I was wondering if this allows me to use signs to sell permission nodes for a price.

Eg: friend want to buy /bcast for $50 but he has $32, when he right clicks the sign it will reply "you do not have enough money!"

friend wants to buy /bcast for $50 and has $152, when he right clicks the sign it will take away $50, give the user the perm node and send him a message: "You have successfully bought /bcast!"

Any help on this would be greatly appreciated, thanks!

 

You can use ServerSigns in unison with CommandsForSale.
/svs add buycmd <command>

This will make sure the plugin checks the player's balance before trying to take the money.
https://dev.bukkit.org/bukkit-plugins/commandsforsale/