Normal Logs all the way. Either Cut them yourself, or rune them from the general store in lumby then bank in the castle. I made about 200k an hour doing this non stop. I did it for about a week, an hour a day, 2.5 on weekends, made about 1.5 mill a week. Only con is that u don't train any skills. If you like a little bit of cheating, create a level 3 account and do it on there while playing on your main.