Usually if a tournament is coming up we will list players or types of players to buy before it starts. A day or two after the start is the time to sell when prices have gone higher and less on the market. Up to you how long you leave it. We are never sure when the tournament will end. Some have been only a few days. Also with the UT servers having so many issues it has created chaos with trading and prices.
However sometimes we might suggest players to buy or types of player such as silver to make profit from in the future. Gambling on a future tournament which we think will arrive. As above we have waited 2 months for this silver tournament but we can now make profits on all those players we bought for just a few hundred fifa 15 coins.
Player prices are lowest on Wednesday evening 5pm – 10pm (UK time) when TOTW (Team of the week) players are released in packs. Because people sell their players in teams to buy packs and also the players flood the market from packs. However be careful of players in Champions League games shooting up in price if they play well Tuesday or Wednesday nights. Generally player prices are at the highest at the weekend when everyone is playing FIFA and games are being played in real life.