I think that makes sense 
We don’t have a full cash report, but what you could do is use project tagging. These be added to invoices overall and would allow you to have a cash and invoice breakdown on each tag.
There’s more information on tags here:
http://community.quickfile.co.uk/t/projects-in-quick-file/1591?u=qfsupport
If you wish, you’re welcome to start a new topic in the ‘Feature’ category requesting this. We’ll then monitor this for interest, and if there’s enough interest we’ll happily take a further look into this type of report.
Hope that helps?