Uncle Sam wants to make it more affordable for Americans to buy their first home. The recent policy changes affect government-backed home loans and could make it less costly for first-time buyers to come up with a down payment or to afford private mortgage insurance. The changes center on the Federal Housing Administration and mortgage giants Fannie Mae and Freddie Mac. The Obama administration has announced that the premium that borrowers with an FHA-backed home loan must pay for mortgage insurance will be dropped to 0.85% from 1.35% by the end of January. The move is estimated to save the average homebuyer $900 a year, as well as help save money for homeowners looking to refinance their mortgage.