Passive investors like those types of investments for both cash flow and appreciation at sale (forced value add is very frequently a large component of the plan).

But that assumption, implies that the rental property you are buying is actually negative cash flow, which is not what people are looking for (unless there is far larger appreciation component than you are giving credit for).  

Deals are made based on two, and only two components:1 - How much the property costs the REI (and this isn't the Purchase Price). 

I am thinking you could cater to Tesla owners / and other EVs  I know as a Tesla owner myself its an important component when I am on a road trip IE pick a hotel with a Tesla charger.

If it’s a part of the main structure and conforms with the rest of the home in terms of building components, heated and cooled sufficiently, etc. it should be included in the GLA of the main structure and should not be valued any differently.

Some component materials are in short supply, so raw components may be more expensive or in short supply.Your best bet may be looking for something in stock at a big box store.

I want to note that ethically, I do not feel comfortable collecting rent from her next of kin so the component of obligation of the estate is largely irrelevant.You are also apparently supposed to secure all of her belongings and note anything that is removed by family members that you allow to visit the property.  

The chips, the components in your fridge etc. are frequently manufactured in multiple countries before being assembled in the US.

My personal one was more simple as it didn't require the Docusign component. 

If you're trying to avoid the emotional component if REI and not necessarily looking to invest where you've got family, it's most often a numbers game and researching markets.