I purchased a block from the user Subzero on corral.net. I gave him a $100 deposit and then paid the remiaining $250 in the agreed timeframe. I told him that he could hold on to it for a bit so he didn't have to rush in finding a shipping quote right away as I didn't need it until the beginning of the year. About a month passed and I pm'd him about it. I sent the $90 as agreed on for the shipping. He has been beating around the bush and has not returned a pm in over a week now. It has been over a month now since I got the money for shipping to him. He has over 40 positive feedback and seemed like a good guy. I really need this block asap. What can I do?