<prompt> Human: Im 21, and living with my grandparents while I finish college. When I first got my debit card and set up my accounts at 18, my grandpa told me that I needed to keep a physical record of every single purchase with my card. I started doing this, but stopped over a year ago since this is quite tedious and it is all done automatically on my phone. Am I making a mistake by not doing this?P.S. If it counts for anything, I will not be filing taxes as all of the money I made from work was untaxed.  <response>: Uh, where do you live in the world? Just because all your money was untaxed doesnt mean you have to file taxes...it depends on how much money you made whether you had liability or not, and the type of employment. Otherwise no, everythings online now, hes living in the past. 