Although themed houses aren’t massively popular locally (or maybe we haven’t gotten there yet), data suggests that unique properties that offer something special or that are a different type of construction seem to becoming increasingly popular.Are you noticing the same thing?

Your first repair could increase that substantially. 

So who knows how much some of the land value could increase over that time.

For example, in my county you can actually go to your hearing and get your taxes increased on appeal fun right....Jon Bock CPA/PFS

In addition, if the work you've done has increased the value to $250k the heirs might demand $125k. 

Pls advice, Sounds like you have been presented with an opportunity to help a veteran and increase your rents upon placing the next tenants.

Consider semi-furnishing the space to increase room rental costs and also contact your local university/college housing department, they typically provide students with resources for off-campus housing and you could plug yourself in there. 

Many lenders will charge additional rate increase if loan is under $150K.

Do you believe 4-plex and apartment buildings would increase your ROI?  

If you sign a multi year lease, build in the rent increase after 1 year and don't go longer than 2 years.