So I know tumbling is a good step to take if sending coins market but what about directly to a vendor? I buy LibertyX -> Electrum on Windows -> tumbler -> Electrum on Tails -> market for my usual purchases. Is this necessary for a direct deal? Or can I go LibertyX -> Electrum on Windows -> vendor's wallet?
I would still tumble as part of my process either way. It's always best practice to do so and, at the very least, it will obscure your wallet address so the other party can't see it. It's quite common for in-person coin sellers on LBC to send through a tumbler just so their customers can't know how much coin they really have and potentially try to rob them. I would think the same precaution should be taken with online drug dealers in relation to blackmail and scam attempts. If they know you have a lot of coin, they may try to take some against your will.