Re the MTZ loans from Zambia, this is what it says on one of the individual Kiva loan pages (
http://www.kiva.org/lend/389468):
Mobile Transactions Zambia (MTZ) is a non-traditional Field Partner, and Kiva's first mobile payments Field Partner. As such, lenders to this loan should be aware of the following:
1 - This loan is due in full in 36 months, however repayments due on this loan are tied to the borrower's revenue, not to a fixed repayment schedule. Each month, 25% of the borrower's revenue will be collected by MTZ, as a repayment on this loan. As a result, the repayment amounts are expected to fluctuate according to the health of the borrower's business. To simplify reporting, the repayment schedule for this loan has been listed as being due in full in 36 months, and all repayments received before that time will be treated as a prepayment.
2 - MTZ will charge this borrower a monthly fee of ZMK 250,000 (approximately USD 50) for administering this loan, as opposed to an interest rate.
It sounds to me like the "25% of revenues" payment all goes to principal balance reduction. A borrower may or may not have a principal balance still outstanding at the end of the three years, depending upon how well the business goes. MTZ gets a flat $50 (appx) per month, which initially is 1% of the $5,000 loan (or a "rate" of 12% if you annualize it), but as the principal gets reduced this flat fee will become a larger percentage of the principal outstanding. It looks like there is no "interest" charged, apart from this flat fee for administering the loan of about $50 per month. I don't believe my prior post said anything inconsistent with the above, though I may have been unclear.
I thought this model might appeal to those lenders who feel that the interest & fees charged by traditional MFIs are "too high."