I'm still relatively new to the trading online world.  I have completed a few trades here as well as through fb I can get references if needed.  I do prefer to use tcg mid as I've noticed the deckbox pricing is a little wonky sometimes.  I do have mostly standard staples but there are a few other format staples as I am now branching into edh and modern.  If I am trading standard stuff for modern I will value the modern stuff a little higher in both coming and going as modern staples tend to be a bit more hard to come by and not everyone plays standard.