ARM versus 30 year fixed

[Neel Iyer]

My goal is to get a conventional loan to buy and hold a single family rental to generate a positive cash flow. 

I am looking for a rule-of-thumb or general advice, not specific to my situation because there are so many other variables to consider -  Given the high interest rates today, is it more favorable to consider an adjustable rate mortgage with a lower interest rate for the first 5 years and then refinance in the future with a hopefully reduced rate, or stick with a 30 year fixed rate mortgage?