How can I set up pre-order pickups on POS?

[keversmcgee]

I've seen questions around the community and am wondering if anyone have figured out a solution yet. 

So, I have customers who come in and purchase an item that is on "Pre-order" and would like to pick it up at a later date or when the item is available. Unfortunately, you cannot do this on POS and you would have to do this on store admin (honestly, not even sure if you can select pickup when creating orders on shopify admin). 

I need this since my customers are kids who do not have credit card and uses cash to pre-order items.

I'm wondering if there is a way to do this via the API or some shopify app that already does this. My current workaround is using webhooks to alter the fulfillment status and add tags to the order to indicate that it's store pickup.

I can invest time to build an app that does this, but managing a store and coding is hard to do nowadays....