It'd have mods. Possible mods:
Camera mod (to see where you're going and aiming)
Hover wheels mod (to replace regular wheels) (this does not make it a flying drone, but just hovers)
Weapon slot mod (can accept gun, crossbow, shotgun or flamethrower only)
Reinforced armor mod (tougher but makes it move slower)
Self repair mod (repairs x% durability when durability is < y%, requires repair kit in its inventory)
AI-controlled mod
Player is still vulnerable while controlling.
It'd have 2 inventory slots (not expandable) : 1) is only for its ammo (can't put anything else) and 2) is only for repair kit.