2Moms is flawless !
I've sold excess supplies a couple of times. They will provide pre-printed labels for USPS shipping. Box your supplies, apply the label, drop at post office and receive payment in timely manner. They provide clear communication with their quotations and make the process smooth. You have choices of payment method - ACH to your bank, Venmo or check. Dealing with 2Moms has been flawless. Highly recommend for best prices and ease of process.