This will be coming from your always on home server...or cloud (Amazon s3)
On the bill itself, change the box32 to your own number, from 1-96, as validation the bill is yours (change frequently).
So the POS point of sale clerk checks atest.png at URL http://boughtupcom.scriptmania.com/cgi/CRcode/test.html
by scanning the qrcode on the bill, clicks on atest.png SubmitQuery,
views the second qrcodes html source code to search for box32 then looks at grid on bill itself, if box 32 is blacked out the bill is valid :)
Inputs Amount_http://URLvalidimage and SubmitQuery to The National Spending Database, Event is instant cash register and account checking.
For more validation scan the second qrcode to go to the API tiny webiste with customers information included...
subtract from yearly total amount $50,000