The most important thing is having a legal agreement that protects all parties and spells everything out.

If someone sues or gets hurt protects all of you too, it wise for you to google pros and cons on LLC, ref inside real estate.

If you would like more protection, require them to get an Umbrella for an additional $1M-$2M. 

Also, it will be a long time before I can actually benefit from not having to deal with the messy wax when replacing them....My main driver for switching away from wax was that there are basically two things that joint comes in contact with (aside from water): poop and wax.  

LLC's do not provide protections against lawsuits.

So, yes, it is fishy, but not uncommon.Why not take this opportunity to switch your banking to a local institution?

I plan on switching to a local driving job when I acquire a property. 

For 28 storage units, I am wondering how you can afford to provide 24-hour protection and access to units for your tenants since I imagine tenants like to have access no less than Monday through Saturday between 8 am and 5 pm and that has to be a lot of labor costs, payroll taxes, etc.

They have switched to kiosks on their front ends, where there used to be 3 to 5 part time kids working the front counter, you now have one.  

That protects them in case you back out/can't close, they don't have to come out of pocket with the homeowner.