the best time for me is 6am to 8am as this is when the better are on market, you need to set a limit on how many tokens to spend, what i do is bid early in the first couple rounds then at a certain round don`t bid to look like i`v given up and bid last second this can be risky though and if 3/4 bidder after say 3 rounds pull out as they will carry on and you save tokens for next player that comes along