From REALTOR Magazine here is an article concerning highter fees for loans backed by Fannie-Mae.  This will effect buyers even if they have perfect credit scores.

Fannie-Backed Loans to Get Costlier
Borrowers with Fannie Mae-backed loans will face higher borrowing costs and interest rates, even if they have a perfect credit score, starting on April 1. 

The agency is imposing a “loan-level price adjustment” on several mortgages, in which borrowers will be charged more in cost or higher interest rate based on how much down payment — or if they’re refinancing the amount of equity in their home — as well as their credit score, explains mortgage expert Bill Gassett in the Massachusetts Real Estate News
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