Brian,
After a fairly lengthy discussion, I think we've come up with the majority of a plan for you.
etotheipi has an awesome powerful wallet, Armory, that will do the majority of what you need to allow
all but the customer's first deposit. You
MUST prevent that from coming from unreturnable addresses as much as possible.
Because of the precise nature of the bitcoin network, you may not prevent the first contact from coming from any address.
Here is the discussion:
https://bitcointalksearch.org/topic/edited-merchant-return-unwanted-incoming-tx-from-green-addresses-74897And here is the basis for the solution:
https://bitcointalksearch.org/topic/m.829711I believe that there is a workable a plan for you to
1) Immediately "bounce" initial deposits received from a Green address that are not associated with a customer account - this is a "best effort" with ZERO guarantee the actual sender will receive.
2) Accept payment from a Green address once a customer has established an account with you.
Armory has more features than I can even begin to test. With the dev to work with you, I think that you can find several ways to better serve your customers.
It will still be up to you to place a very strong warning on your website for new customers
sending initial deposits from any shared type wallet, such as an exchange may result in the loss of fundsIMO, if we can setup a plan for you to immediately bounce payments w/a message there is a much greater chance that your customers will not lose incorrectly sent initial deposits. (anything is much greater than 0%!)
I'd like to recommend that you contribute the 10BTC bounty to etotheipi. I believe that he is intrigued by the project, and will assist you in configuring things. (Perhaps you might kick him more if he spends some time assisting you guys)
Since I build & deploy systems, I'd be very interested in the project as well. I'd learn a great deal.
I'm also going to kick etotheipi some coin for patiently understanding the need, explaining a solution, and the hard limits of the solution, without thinking there was a desire to change the design of the network
EDIT: Important infos:
http://bitcoinarmory.com/1QBDLYTDFHHZAABYSKGKPWKLSXZWCCJQBX << Armory Donations