Pay off my mortgage or invest?

[Jonathan Studdard]

I have 30 year mortgage (rate is below 4%) on my current residence where I've lived for about a year. I could pay it off (I owe $185,000) and have about $10,000 in emergency savings leftover. My family thinks I should pay it off then save because my wife and I are business owners without guaranteed financial security, but I read that with my low rate mortgage I could grow wealth faster with responsible leverage, but this is a hard sell to my family who has 0 interest or faith in REI. Should I pay off my entire mortgage and keep saving for a second investment property, should I pay down and refinance my mortgage and invest/save the rest, or can I start cash flowing enough to cover my living expenses without being a REI pro?