Select different credit card for work related App store purchase
I just found this on Google searching for the same thing. I wanted to buy a $50 app that I'm using exclusively for work purposes (Things 3), and wanted to use my business card to feed it into Quickbooks and write it off.

Unfortunately, as of today, you're going to have to create a separate Apple ID associated with your business/business credit card. I'm a developer so I basically already had one set up to develop iOS apps with my business card.

Once you do that, on Mac OS, in the App Store app, just hit Store -> Sign Out, and then sign in with your business Apple ID - buy your app - and then switch back.

Apple should make this easier but I bet the number of people buying business related apps that they want to write off is like 1% given the number of people using it for personal purposes.

As far as like, sharing the apps between your accounts - that I'm not sure about. Once I bought this app, it just works, and lives on my Macbook. The family account sounds like a solid option to explore.

Hope that helps you!