I was thinking about the traditional wizards staff and it got me wondering could one object serve for multiple foci? For instance a staff or other melee weapon enchanted as a weapon foci and a power foci so it enhanced both your magical and mundane attacks?
Yes. SR4 had rules for what were called "Stacked Foci," which IIRC there was mention in SR5 material but no rules given. They were otherwise pretty simple, rules wise.
Choose and calculate the karma and nuyen costs for each part of the focus you want, say a Force 3 Power and Force 3 Weapon focus staff. All costs are the sum of the parts:
The karma cost to bond this focus is 27 (Force 3 Power is 18; Force 3 Weapon is 9).
The monetary cost to buy this focus is ¥75,000 (Force 3 Power is ¥54,000; Force 3 Weapon is ¥21,000).
The availability to acquire the focus is 24R.
The Force of this focus when activated is 6, and counts as a singular focus when activated and all other tests (like addiction). You may not activate individual parts; it's all or nothing.