New data from real estate agency OneKey MLS shows that the median price to buy a home on Long Island took a dip in October. In Nassau County, the median cost for a new home was $837,000- a 1.4% dip from September. In Suffolk, it's $701,000- down more than 2.5%. One thing helping buyers seal the deal on a new home is adjustable-rate mortgages. The loans can provide people with lower interest rates and more affordable monthly payments. Economists say the amount of buyers taking out adjustable rate mortgages has tripled in the last five years. There is a catch to those lower monthly payments. After a few years, an adjustable rate mortgage will reset with the current market. That means if rates rise, a homeowner's monthly payment could too.