In a Chapter 7, all fees must be paid before the case is filed, but we certainly allow payments to be made over time as the work is done prior to filing. In Chapter 13, you can often pay a portion (or in some cases none) of the fee up front, and pay the rest through your plan. And many bankruptcy attorneys (ourselves included) accommodate clients work schedules, as the last thing you need when facing financial difficulties is to lose more time from work.
My office will gladly take payments in two or more installments, but all fees must be paid prior to filing the petition as indicated in the other answer. The reason for requiring full payment is that your outstanding debt to your attorney could be discharged with your debt in a Chapter 7.
If your circumstances warrant the filing of a Chapter 13 then our office would offer more flexibility in payment of legal fees, as a Chapter 13 is similar to a payment plan vs. Chapter 7 where you pay nothing to your creditors.
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