Having direct experience in being a third party payment aggregator, here's some notes based on this post and their FAQ (if anyone cares): 1. Fraud will now be

Having direct experience in being a third party payment aggregator, here's some notes based on this post and their FAQ (if anyone cares): 1. Fraud will now be your #1 issue (if it isn't already). People will make fake Etsy accounts, add fake products, and then make "purchases" using stolen credit card numbers. They will have the $ deposited to an E*Trade bank account, a pre-paid debit card that accepts ACH, or use some rube's account they found on Craigslist. Most of the time, you won't catch it until the money is already deposited. Then the chargebacks start coming. I don't have the luxury of having a $50M warchest of VC money. You will definitely have to spend money and engineering resources towards this soon. 2. Based on your FAQ, you're requiring sellers to mark an item as "shipped" before depositing their money. We actually had to turn this requirement off because it annoyed so many sellers. When a seller gets an order (in our case, photographs), getting it fulfilled becomes their focus. Making them go back to the web and mark it as fulfilled is something they will often forget. Getting their money deposited is something they won't forget. IMO, I would try to make this more automatic. Use something like Twilio to send the seller a text 5 days after the order ... "Has order 24039 (yellow scarf) been shipped to Suzie J yet?"