Chapter 13 is very similar to chapter 7, in that it is usually for consumer debtors,  but here the debtor is paying what he or she can afford for a period of 3 to 5 years, depending on circumstances.  In consideration for these payments, the trustee does not liquidate any of the debtor’s assets and a broader discharge is granted at the conclusion of he case.  We do these kinds of cases for a flat fee, but usually do not require that it be paid in advance.  One of the common features of chapter 13 is the requirement that the debtors give it their "best efforts" over at least a 3 year period of time.