Microloan Modernization Act of 2017 This bill amends the Small Business Act to repeal the "25/75" rule under the Small Business Administration (SBA) Microloan Program (assisting low-income individuals to start and operate a small business) that permits SBA-designated microloan intermediary lenders to expend up to 25% of the intensive marketing, management, and technical assistance grant funds they receive from the SBA to provide information and technical assistance to small business concerns that are their prospective borrowers. The total amount of loans outstanding and committed to any particular intermediary (excluding outstanding grants) from the SBA business loan and investment fund shall be increased from $5 million to $6 million for the remaining years of the intermediary's participation in the program. The SBA shall: compare the operations of a representative sample of eligible intermediaries that participate in the microloan program and of eligible intermediaries that do not, study the reasons why the latter do not participate, recommend how to encourage increased participation by intermediaries in the microloan program, and recommend how to decrease the associated costs for intermediary participation. The Government Accountability Office shall evaluate: SBA oversight of the microloan program, including oversight of participating intermediaries; and the specific processes the SBA uses to ensure program compliance by participating intermediaries and overall microloan program performance.