Things I got in preparation for the development. 

• nRF52833-DK this is development board for the nRF52820 
• 2.7" e-Paper HAT - Waveshare
• RV-3028-C7-EVALUATION-BOARD from Micro Crystal AG (this one I got for free from their website, the have free samples)
• MCP73830L Evaluation Board
• I had W25Q64J lying around, just put it on a adaptor board and got myself a dev board for it.

Having those things, gave me the ability to work on the software, before I had my board made. One down side about working with dev boards is that jumper wires are messy. They can pop off and you have to double check connections often.   

Another crucial thing about having all of this stuff is, that I will have at my disposal hardware I know works 100%. When I am not sure if the problem is hardware or software I can always go back to my mock up and test.