Each loan type has its pros and cons!

1. A fixed-rate mortgage has the same interest rate and monthly payment for the life of the loan.
2. An adjustable-rate mortgage, or ARM, is a home loan with an interest rate that can change periodically. The initial interest rate is lower than that of a comparable fixed-rate mortgage. 
3. If you plan to own the house for only a few years, it can make sense to take the lower-rate ARM because you will be moving before the adjustable rate period begins. Your payment and rate will be lower, and you can build your savings or more comfortably afford a higher priced home.
4. When interest rates are relatively high, ARMs make sense because of their lower initial rates. When rates are relatively low, fixed-rate mortgages make more sense. Borrowers can lock into these rates and still have the option of refinancing later if rates go down more.
5. When I bought a Cambridge 3 family building in 2016, I took advantage of a 7/1 ARM and refinanced later into a 30-year fixed rate loan when rates went down.