If you look closely at hospital rooms you will see wide doors, metal door frames, chair rail all around the room, hard surface floors, and rubber cove base for baseboard, .

The problem I have is the driveway to access the parking area in the rear of the house is very narrow ~10feet wide. 

This will vary widely from market to market, depending on Zillow's access to market data. 

The added benefit is I get a good sense from a wide range of properties are available.

I've closed with several others and haven't had widely varying experiences so you should be just fine if you go with somebody besides these two. 

Varies widely by area so I can't say, but since I'm in California and you are in Pennsylvania, your numbers should be higher than mine, potentially much higher.

One reason I don't like it is the values can change from day to day with pretty wide swings. 

I also believe you will get a wide range of advice.

I just wanted to know if this is a widely held industry standard or something this particular investor brokered through a relationship with a local bank?

Just like any new endeavor you're going to want to go into eyes wide open and learn as much as you can beforehand.Please look up investing in Self Storage on the internet - lots of articles, videos, etc.