I would just advise you to just avoid arbitrage betting. Sports bookies are getting smarter every day and since most bookies don't allow arbitrage betting, you can get your account locked. They will know you are betting an arbitrage quite easily, because usually arbitrage betts will look like this
0.0325478652BTC on GSW -10 @ 1.95
Which totally gives you off that you are arbitrage betting and hence you can get banned an your balance forfeited.
I agree, there are been people who got busted with this and got their accounts banned or blocked then their balance was confiscated by the website which is totally bad. You should really consider that risk if you are really going to do this. But, well, good luck man.