Have a little suggestion 
Been running through DDE scenarios in my head, and was thinking that newbies might be a little confused at first as to what amount each deposit should be set at. How difficult would it be to set up a dynamic “recommended” DDE amount that changes based on the product/services value, both user’s reputation and each party’s risk tolerance
…could also factor in user account balances and recommend using the actual item or service as collateral if one party cannot meet deposit requirements
(similar to password strength recommendations when creating new internet accounts etc.)
of course still allowing custom/manual tailoring if desired too…
