Restyling of fees in consumers credit and their optimization

The structure of fees in a consumers credit contract is considered. It is analysed under the profile of its financial convenience (measured by the net present value (NPV)) and the legal profile, requiring to declare the internal rate of return (IRR) after fees. We characterise the fees structures allowing for both an increase in the NPV and a decrease in the Internal Rate of Return. We provide also the description of optimal fees structures by solving an LP problem. Finally the problem of financing initial expenses is considered.