i built 20 different gametime 84s, linemen, linebackers, corners, te's mostly, they cost about 90-100k to build depending on what's available (82s for under 34k or gt 80s under 12k and reg 80s under 10k), the msot i ever spent to buidl them was 105k. sometimes there are snipes that help offset paying a little more other times.
avg build price is around 95k.
i list them all for 135k (occassionally a little more or little less depending on the market), doesn't matter if there is one up for 105k. net profit per sale is around 25k. some cards sell way more than others (the guards, jags and saints CB and Parham sell the most). once all the work was done building 20 different ones, i would just rebuild the same card and keep the same 20 cards up.
i dont sit on the AH, i check every 60-90 minutes.
i just hit the 2m mark for doing this. an avg hour for 20 listings sells 10-12 of them. done with this method for now and sold them all off at 119k to be done.