Software/App for organising my invoice/PO/quotes etc.

[megaphone]

I run a small business. I use Wave for my accounting which is fine for my invoicing and accounting.

I'd like to keep a separate copy of my invoice together with the PO sent by my customer and the payment advice and maybe some pictures and a copy of any quote, associated emails etc. I suppose you'd call it a job/project file.

Any recommendations on the best way to do this? Any software/app that will do this easily for me? Needs to be for Mac and possibly iPhone.

I currently do it manually into files which works but i'd like a smother process if possible.