There are three separate elements to the cost of a bankruptcy.
1) Attorney fee: Amount varies.
2) Court filing fee: Currently $338 for Chapter 7, $1,738 for Chapter 11, and $313 for Chapter 13.
3) Two credit counseling classes: Currently $35 grand total for both classes (per person and per married couple.)
Regarding the attorney fee, in my practice the amount depends on the complexity of the case. More complex cases cost a little bit more, and less complex cases cost a little bit less. Once I have some information from you I will be able to give you a quote.
For a Chapter 7 bankruptcy you may pay the attorney fee in one lump sum or in installments before the case is filed, the choice is yours.