Conventional mortgages are those not insured by a government agency — and to get one, you usually need to put 20% down, and they’re usually only 30-year, fixed rate. If those terms don’t fit your needs, then you can consider an FHA guaranteed loan, and if you do, you need to know a few things. wrote a nice introductory article covering five points about FHA backed mortgages. It covers everything from current down-payment requirements to some more surprising items, like FHA mortgages may be easier to re-finance.