My own experience. Everything over 2% is too much.
Most merchant providers will close accounts with over 1% chargebacks.
Of course it depends on the business relationship you have with them.
the chargeback rates totally on hard the rebill is and how the customer support is... + how is the cancellation policy etc etc... there are a lot of factors that need to be considered... u cant just put a number on it...
this question is like those "how much do you make?" questions... dumb