Pro tip--make sure your exhaust fan in the bathroom is vented to the atmosphere--meaning out to the outside.....go out the roof or out the side of the unit or secured to an opening in a soffit vent grille off the house. 

The roof and gutters are only a year and a half old.

In my area you have to strip the roof shingles at a minimum . 

I hope you or someone is at least keeping an eye on your properties for break ins, squatters, roof leaks, temperature control, frozen pipes (if in cold climate), if you have a basement and sump pump goes out leading to water damage etc.I just talked to two investors in California that have let their properties sit vacant (no mortgages so paying property taxes and insurance).

A roof on the 600K property will cost more than on the 300K property, but you have more roofs to repair on the multiple 300K properties.

Large basement and attic space, new roof and some of the kitchen is already torn out from the current owner. one bedroom does have a closet that will need built. plumbing seems fine, maybe a couple angle stops to change.

I also want to clarify that I do still keep a decent amount of cash - just not enough to cover every single property roof at the same time if that ever happened for some reason. 

Boots on the ground is critical.

I'm not how you are defining a BRRR that works, but if I have a unit with brand new roof, mechanicals, kitchens, bathrooms, etc... and leave 10,15 or 20% in the deal I still feel like I'm winning.  

It also kills two birds with one stone: an investment property, and a roof over your head.