They have obviously placed you in an exceptionally high risk category. In the past, I've had clients who are selling high risk items and high ticket items, but they've never been asked to have a reserve that high!
I've also never heard of a car accident affecting your credit history. It's usually because you've got a CCJ, or not kept up payments on your CC or mortgage etc...
If your own business bank won't give you a merchant account, then you will have some problems getting one anywhere else at a reasonable rate....
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