Betting rules
To avoid mistakes with comparing bookmakers' odds you must know the exact the rules of accepting bets (surebets) and payments of all bookmakers.
Most rules regarding sending coupons is similar. Slight changes may, however, lead to losing to one bookmaker while the other returns your bet money. An example of that can be betting on a tennis match.
An example of a tennis match:
The first bookmaker, for example: Bwin has in his regulations that after playing one ball, the match must be decided.
The second bookmaker, for example: Pinnaclesports regards the match as decided after two sets are over.
Let's analyze this example, let's say that in a match between:
- contestant A(we're bidding for him on Bwin)
- contestant B (we're bidding on him on Pinnaclesports)
the first contestant had an injury in the fifth game.
According to the first bookmaker the second contestant won (the first ball has been played) - we lose our money.
According to the second bookmaker the match isn't decided (the second set didn't end) - he will give back the money we bet, not the expected winnings.
All in all, we witness a loss. Of course, the injured player could be contestant B, in which case we would get our winnings from the first bookmaker and our money back from the second but that's more of a lottery than a sure victory.

