I currently have 12 units consisting of 8 properties and the amount of inventory/equipment I am maintaining for the properties is starting to stack up. 

They equip their negative statements with anecdotes of past bad experiences.

I'll go past there later today to see if they've moved the heavy equipment out. ofgift

I don't mean to sound harsh but think about how that is going to sound to an adjuster when your house has a fire started by the tenants electronics equipment.  

If there's exterior access you might consider putting a keypad lock on it and setting up storage stalls down there.You can market it to the crowd you were initially thinking of to store their ski equipment in the off-season.This is probably the cheapest reno you're going to get away with since you can just frame in what you need.

Electric and water off and slowly safely start "demolition" (removing sinks and toilets fixtures) running as much noisy equipment as possible.

Our lease does not permit the tenant to affix anything to the building without our written permission; and then we require it be done by one of our "sanctioned" service providers.The first time we renovate a property after acquisition, we install conduit (with a pull) for the various service providers to the basement or equipment room/closet.

Each unit comes with a fully equipped kitchen, gas wall heaters, wall mounted AC units, large bedrooms and living area, and plenty of on-site parking.

Then financially, you need to be equipped for this.I avoid HOAs unless it's an extremely unique property.

This will leave you better equipped to finance fast growth.