We have a zero balance account set up with auto transfers into our checking. The key is that there is also an ACH block on outgoing transfers. Took a while to find the right guy who understood what I wanted.

They did not want to do it, gave me all the reasons not too, yada yada, but finally did it.

I have my boat listed on ebay as well. Just the other day had a guy from Germany send me a message about doing the exact same thing as whats going on with you now.

I was very skeptical and didnt take it any further. Maybe same guy. Be careful.