Mutual fund houses are strongly resisting a proposal from market regulator Sebi for treating small investors at par with large institutional ones in terms of various charges, such as exit-loads, with the argument that retail investors are costlier to service. Sebi, in its latest communication to about three-dozen fund houses operating in the country, has suggested that they charge equal exit-loads, which are the fees that investors are asked to pay when redeeming their mutual fund investments, from both retail and institutional investors. They are asked to pay one per cent of their investment value as exit-load, as there are no charges.