Condominiums are becoming more difficult to purchase and refinance as lenders increase fees and tighten regulations to offset what they say is the higher risk of lending to buyers of condos as compared with buyers of single-family homes.

The changes are part of an effort by mortgage giants Fannie Mae and Freddie Mac to limit risky lending in a segment of the housing market particularly hard hit by foreclosures in recent years.

In addition to paying higher fees to get a loan, prospective buyers now must make down payments of up to 20 percent because companies that traditionally insure lenders against borrowers who default are shying away from condos.

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