Thanks everyone for the comments. We do intend to sell our current residence in 5 years, thus considering refinancing into 5 ARM interest only, in order to lower mortgage and come up positive when we rent it out. It is not a investment property at all, since we are not building equities. We only hope the house market will pick up in 5 years, so we lose less on this one. As for our planned new purchase, we will definitely take fixed rate.
