This is all hypothetical and does not relate to any true events ;)
Hypothetical scenario... The hypothetical user has a DNM account which has been used for personal use. The account has been funded on a number of occasions by direct BTC transfer from a regulated and ID verified BTC account. User then decides to become a vendor. User opens another DNM buyer account, then funds it with a direct BTC transfer from the original DNM buyer account and turns it into a vendor account. For some silly reason, user sends a test BTC transfer from the verified BTC account to the new DNM vendor account, then sends it straight back to the verified BTC account (only small amount). A few items are listed on the vendor account and sold. BTC profit transferred from vendor account directly to original buyer account to make a few more purchases. Step 4 and 5 repeated a couple of times. User then does a little research into bitcoin tumbling. User transfers all funds between the 2 DNM accounts into a reputable tumbler account. User worries a little about the initial funding and any possible link to identity via the verified BTC account and blockchain. User also worries that home address could be revealed if LE were to link the vendor and buyer accounts in future.
Hypothetical notes to this hypothetical scenario: The original established buyer account may have had one or more instances when a purchase was made and home address revealed without PGP. This has been well and truly deleted, but if DNM is compromised could be recorded. PGP, VPN and Tor used at all times other than mentioned above. At this stage we are talking about fairly small transactions an not a great deal of vendor sales. Vendor would really like to keep the same vendor account going as it has a lot of good feedback.
Hypothetical questions to hypothetical scenario: Does the user need to worry about anything in this scenario? Should the user/vendor start over again and fund new accounts using tumbled coins? Should the user always tumble when transferring between vendor and buyer accounts or only when cashing out?
Sorry for the the long post, but these are the only real questions I have that I can't seem to find an answer for.
If you are serious about vending, and especially if you expect high volume, you need to start a new account and cut off all ties with that mess.