Buying a property for my parents

[Douglas Gross]

My parents are moving to Florida, where I currently invest in SFHs. I would like to buy them a house, most likely in a 55+ neighborhood (I am not 55 years old, but they are :)). I am looking to put down as small of a down payment as possible and they will be "permanently renting" the property from me (paying the mortgage). 

Until now my primary residence was their old house, which was now sold. I am overseas now for an extended period of time and I guess that means I have no primary residence. Can I get an FHA loan with a low down payment for their house if I claim it will be my primary residence?

Any other suggestions as to how I can go about getting a conventional loan with as little money down as possible? Any help is greatly appreciated.