Idea for a method of more privately buying/selling BTC

[theymos]

This idea just occurred to me. I haven't tried it, so maybe something makes it impossible.

1. Buyer wants to buy BTC from Seller.
2. Seller secures the BTC in a 2-of-3 multisig escrow along with Buyer and a mutually-trusted escrow. (A 2-of-2 no-third-party escrow could perhaps be used instead if the Buyer already has some BTC to use as collateral.)
3. Buyer buys an Amazon gift card at a physical store using cash.
4. Seller indicates to Buyer a nearby Amazon Locker location, and signs this message with a key known by the escrow to belong to Seller.
5. Buyer creates a new Amazon account with a fake name near the indicated Amazon Locker location, and adds this Amazon Locker to his account.
6. Buyer uses his gift card to send something money-like to the Seller's Amazon Locker. For example, physical gift cards or gold could be used.
7. Buyer forwards the Locker code to Seller. Seller picks up the item and releases the BTC to Buyer.
8. If Buyer fails to send the item, the escrow can release the BTC back to the Seller after a time-out period. If Seller fails to release the BTC after receiving the item, Buyer can prove with near-certainty that he held up his end by giving the escrow the Seller's signed message indicating the correct Locker location, along with Amazon's DKIM-signed Locker-code email. Theoretically, Seller could intercept the delivery before Buyer gets there, but this seems pretty difficult since the Locker is likely to be far from Seller. If necessary, some TLSnotary stuff could probably be added to reduce this risk.

At the end, no info about the participants is revealed except for the very-approximate location of the Seller. (And perhaps Amazon has some way of tracking the very-approximate location of the Buyer based on where the gift card was purchased.)

Buying the gift card and shipping should have no cost. The overhead will be in converting the item back into cash. With gold coins it looks like it'd be about 18% overhead, which is pretty bad, though still often better than the localbitcoins spread. Maybe you could find something that is more efficiently convertible to cash than gold coins, or the Seller could ask to receive things that he actually wants from Amazon.

This is better than just giving someone an Amazon gift card code because:

- It's innately irreversible.
- Due to Amazon's DKIM signature, the transaction is more easily provable -- the escrow has to do very little thinking in case of a dispute.
- Unless a gift-card-code recipient takes unusual steps, this way is more private.

[tmfp]

This idea just occurred to me. I haven't tried it, so maybe something makes it impossible.....

There doesn't appear to be much wrong with the logic.

Maybe you could find something that is more efficiently convertible to cash than gold coins.

Let's think, something small and easily convertible into cash that has a recognized street value.....

[OgNasty]

This sounds very similar to purse.io.

[BingoDog]

It seems possible but still rather complicated with so many steps and conditions. Isn't it easier to find some trader on localbitcoins and make the business? You can buy bitcoins there pretty anonimously, at least with traders in my country and the transactions are quick and simple.

[hardtime]

It seems possible but still rather complicated with so many steps and conditions. Isn't it easier to find some trader on localbitcoins and make the business? You can buy bitcoins there pretty anonimously, at least with traders in my country and the transactions are quick and simple.

Yeah, I've read through this entire thing and it would help with anonymity on the site itself and for the buyers and sellers but it would just cause unneeded work and confusion for people why just want to get a simple trade done. Plus, on a site like Paxful and LBC most traders are only going to want the AMZN card itself and confirmation it was bought with cash.

A simple receipt can confirm the card was bought with cash and you're done, no need to go through any crazy ideas and such. Only thing you're going to be opening up to lose anonymity is your IP address.

[Quickseller]

3. Buyer buys an Amazon gift card at a physical store using cash.

I am not sure how this can be enforced. If a buyer wishing to commit fraud were to purchase AGCs via stolen credit cards (or other fraudulent means) to be used with this transaction, then #7 would involve the seller being caught on camera picking up cash-like items that were effectively purchased via fraudulent means. The fake name used in #5 might lead Amazon and/or Law Enforcement to believe the seller intended to launder money via stolen credit cards (or other fraudulent means).

Although the transaction would likely be anonymous if the gift card was purchased via legitimate means, if a gift card purchased via fraudulent means is used in the transaction, then Law Enforcement might figure out who the seller is, and the transaction would likely be frowned upon (due to the gift cards being purchased via fraudulent means).

6. Buyer uses his gift card to send something money-like to the Seller's Amazon Locker. For example, physical gift cards or gold could be used.

The Amazon merchant could ship a roll of quarters instead of gold coins. This would generally be unlikely, although if the buyer was conspiring with the merchant, then the seller would be at risk. Step 5 might make complaining to Amazon complicated, especially if they ask you to sign an affidavit that what was ordered was not what was received.

I believe that purse mitigates this risk by forcing the seller chose the exact items.

8. [...]. Theoretically, Sellerbuyer could intercept the delivery before Buyerseller gets there, but this seems pretty difficult since the Locker is likely to be far from Seller.

A buyer who wishes to commit fraud could potentially target a seller who is local to him.

A wish list on the part of the seller would probably resolve this issue, although I am not sure if wish lists are compatible with shipping to an Amazon locker. If you assume that Amazon lockers can be used with wish lists, then the seller would create a wish list, then the buyer would purchase items on the wish list; the buyer could prove that the item was delivered with the order history of his amazon account (I think).

With gold coins it looks like it'd be about 18% overhead, which is pretty bad, though still often better than the localbitcoins spread.

I would be happy to buy BTC from a seller looking for privacy this way. Since I do not have an active need to buy BTC anonymously, I would want the seller to cover all of the overhead costs, and I would want to get to buy the BTC at a discount (based on the amount of cash I need to use to purchase the gift cards) to compensate me for my time. I believe that it would be likely that one party to each transaction would likely be in a similar situation.