I recall a mate of my Dad's who apparently only ever used to put bets of £200 on the horses - never more, never less. Apparently he made his living at it. He used to spend a lot of time studying form though him and my Dad to a lesser degree were a part of a network that got given tips on the regular. Him and my Dad dropped me at University one year - they drove up to Nottingham to try some scam on at the local bookies, that involved miswriting numbers 4s as 9s or something like that. I think they did alright that day.