I think it may depend on how many calls (or whatever the term is) the bot makes to the free betfair api. If you set your bots up so that they don't make too many calls then it may be okay however that means the bet placement could be delayed and you miss out on your price. It could also depend if you will be betting under their minimum as then it is making heaps of calls just to place that one bet. (Also BF could ban you for this).

With the bot I use they won't let you have two running at the same time on the one account as I believe that may cause the bots to play up.

I got around this by my wife opening an account.

Also with backing instead of laying you have to pay the turnover charge, on the markets that still have that, for each and every back bet.

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