The industry standard for used cellphones is 80% and more. We believe it's way too low.
At Celeri.ca, we are engaged in providing phones with a battery that holds 85% and more of its original capacity and that have less than 500 charging cycles. Therefore, we will replace any battery that doesn't respect these criteria before putting the phone up for sale.
Please note that in some cases, we can't reset the battery cycle count to zero when replacing the battery. It's normal and won't affect the lifespan of your new battery!