When I was 21 I partnered with someone and we bought 2 apartment buildings with 14 units.

They complement LLC as a tool in asset protection strategy - do not confuse them as a replacement.The number of properties per LLC should be based on a number of different factors: equity, number of units, cash flow, location of real estate, and tenants. 

The other is a mobile-home, worth almost nothing, that brings in twice as much money each month due to being paid off.  

I’ve also managed units where on our renewal rate we did reduce the rent from the prior year, but for other reasons, such as the prior year of the tenant having a washer and dryer, and a major plumbing issue with the building, preventing us from offering it the following year so we did a reduction.

I aiming to sell myself my first multi-unit property. 

Hell, ~99% of mortgages in United Kingdom, Finland, Australia, Ireland, and Canada are short term, variable debt.

New AC condensor unit.

New AC unit.

New AC condensor unit.

The rent would likely increase as new developments in the area add more expensive units but comps are all suggesting 1500 for a similar size updated SFH