$500 via Verizon e-gift card (sent w/in 8 wks). Activation of 4G LTE/5G phone on 5G Get More plan req’d. Device must remain active for 45 days. $500 charge back if service cancelled w/in 12 mos or eligibility req’s are no longer met. See vzw.com/bring-your-own-device for details.
I mean, to be the safest, you can print a copy of your bill and gather it with many other bills to be stored in a file cabinet. Maybe put the cabinet in a climate-controlled room... I don't think that's necessary.
One time I cannot find a receipt, or legally a proof of purchase, to receive warranty services. I went back to the vendor for this very purpose to ask a duplication of the receipt. Luckily, they were able to reproduce it.