Sports betting arbitration takes extreme patience for a number of reasons. First, there are not many arb's that appear on a daily basis and you'll find that once a sportsbook realise what you are doing you'll get your account limited very quickly. Secondly, you'll need a big bank to make it feasable as you'll be looking at making 1-2% per bet and there isn't always the liquidity you might need on the exchanges. Finally, there are times that you won't find an arb and you'll need a lot of self control to not have a bet at these times.
Good luck though, if you have the patience you can make money.