I have some successful investors

They don't have to have very good income. But they do have something in common. Here is what I found after I talked to them:

1)They prefer to buy local properties. It's easy to manage. You don't have to go to FL, AZ or TX to get rich. I have one customer purchase properties in SF in the past 4 or 5 years. over 2 mil equity now.

2)Better to be a handy person. If you are not, you should better learn. Otherwise, it will cost you more money to repair.

3)purchase the properties one by one(not several at the same time). Get one little rental first, have some "hands-on" experience about how to deal with the tenant. If you feel good, then move on. So then you will either purchase more properties, or sell them and back to one primary.

4)Move to the triplex or multiple units if possible. Cash-flow is better for those mutiple units. Then commercial, then land, etc.

5)When you plan to be a landlord, think for long term.
Don't expect to buy it and make millions a couple of years later. For the mortgage, better to get 10 yr fixed or 30 yr fixed. Usually you have to pay closing cost for Rental Properties.