It cost me about 10M ISK and 50 odd jumps on 2 Toons, but I have the name of my new trade adversary.
(Manipulate prices until one of their hull buy orders was within 5M of Jita price. Fly my main to Jita (he was the only one able to fly that hull), buy one, and return. Move one of my out of Corp Price Check Alts to a nearby station. Transfer the hull to them so it doesn’t have my finger prints on it. Sell to their buy order. Move my Price Check Alt back to its trade hub.)
They are 21 months old, and haven’t moved out of their starting NPC Corp. Their updates were infrequent today, and they seem to only log in for short periods then log off. It doesn’t appear to be a main – but one of possibly many trading Alts. I’d guess the speed at which they identify what orders they need to change suggests at support from 3rd party software.
Combating this one will likely require a lot of stamina.