Integrated an advanced inventory system in a/your F4 Menu's

I've seen a lot of F4 Menu's here at ScriptFodder, but I think they're lacking some basic... "Inventory System", sure you can get another script that allows you that BUT, why not make it easier to integrate it into the default F4 Menu and in those who have made F4 Menus aswell? Instead of you get a new SWEP to open it or another command, and menu etc. Maybe donor ranks can get X amount more inventory space, you can sell items from there, maybe even storage your car there, so you don't have to go to the car dealer, that is 100 miles away.