For guests, if it checks the "W/D" box then whatever fits will be fine, I don't think there is a true minimum.

Being that I'm so new in the field, I am trying to think outside the box to find this type of buyer.

A cursory Google search shows that you’re right: in most jurisdictions, unlicensed persons can’t open doors.

I’ve been searching for deals but haven’t had much luck so far.  

Search Google for "file ethics complaint [STATE]" and you will find instructions for filing a complaint against the property manager.

I had to really search for them this year, but here they are. https://www.kohls.com/catalog/toastmaster-small-appliances-k...Each are on sale for $16.99 with a $12 rebate, making them only $4.99 each. 

Imagine what our grandparents paid for TVs relative to their income, for a 12" BW box inside a cabinet that weighed 300 pounds, especially in today dollars . .. . 

My other project years back was searching for active businesses to buy, at one time laundromats, many located downstairs in mixed use properties. 

Here are a few suggestions on how you can maximize the wealth of information available: Check out the blogs and podcasts, or take advantage of the search feature (magnifying glass).

A simple search on a service like Propstream will show you what properties have them.