Looking to get some insight on how you manage PC accessories and peripherals for your new hires. Does the new hire pay for everything themselves (aside from their PC and mobile phone) or do you give them stipends of a certain amount?  Do you choose accessories (like headsets, mice, keyboards) for them? How often can they order replacement accessories like a new headset? How often do you review compliance to spend policies from every department?

In our company we do not use BYOD and employees can, depending on the employee's function, choose from among PCs from a positive list and choose accessories from a positive list. 
new accessories can be ordered when needs change or when it’s broken. 

We provide the necessary tools for working, laptop, mobile, headset, mice, a little docking station when new hire is onboarding. This facilitates standardization (and service desk activities). in addition is helpful in vendors' negotiation about these tools.
Laptop can be replaced after 3 years, the accessories don't have a time ... but they need to be back to the company if people will leave.
People can ask some other accessories (video, special chair...) if they need for healty reasons.