u/SquishyPotatoes11

Hi so I (30F) have a HDHP and some pretty high medical costs. My plan is to pay them out of pocket and invest my HSA (which I am maxing) and eventually cash in my receipts way later once my money has compounded. My question is about receipts and what I actually need a record of. I have a medical bill that is $1018, I set it up on a zero interest payment plan for $105 a month. Do I need a receipt for each of my 10 recurring payments? Or just the original medical bill/ invoice?