If you buy a rental property most anywhere in the USA that isn't a hardcore ghetto for at (or below) it's fair market value and hold it for the duration of your mortgage, it's very hard to lose money.

A General liability policy will keep you covered in the event that someone tries to drag you through a lawsuit or you lose business income due to a loss.

Especially in small multifamily as you lose economies of scale.

Lose your tenant and now they're no longer paying your mortgage...that high monthly payment is coming out of YOUR pocket. 

The downside here: I don’t have $600K to put down as a down payment for all of the properties and I don’t want to lose this deal.

It's still pretty liquid if something goes south, but at least it's appreciating and building value rather than just sitting in a bank account, losing value due to inflation. 

The down side is that your properties are all now treated as one... you lose flexibility to refi or sell them down the road. 

You bet big, you can lose big.If your wife is onboard with all this, start slow and see how you both like it.Find out how much your current home will rent out for - and then use 90% of that for your estimates.

@Victor FunesIf your conservative you’ll likely lose less money if something goes wrong. 

1) they don’t want their tennants who might not be financial secure to lose everything they own.