Go into it with your eyes open, and read about all the mistakes people make here and add to your systems to prevent those mistakes from happening to you.
Now as far as milestones that made my life easier there are a few that stick out, the majority of my renters are students so YMMV
-1 dwelling unit, one rent check no exceptions.
-E-payments, I do not accept paper money or direct transfers of any kind(in the early days Venmo, now a new system..)
-Docusign leases
-Stopped chasing the cheap handyfolk
-Innago or similar. I can screen tenants with a custom application, e sign a custom lease, accept deposits ACH'd to my account, and then accept rent payments ACH'd to my account. Also I can send bills and it automatically tacks on late fees and sends tenants reminders.
You won't regret passing on a tenant, but you WILL regret making an exception.
Treat tenants how you would want to be treated yourself no matter how frustrating they are, they are your customers. It may be your house, but it is their home.
Don't sweat the small stuff. This is a lot easier if your cash flow is good.
Be specific when dealing with tenants
If you have more specific questions myself or someone else can probably help
