Quote from @Dereck Olson: Hi Nicholas,  Just a thought from the possible tenant's perspective, but filling out a prequalification form and/or providing personal information before they have even seen a place and know if they will be interested in living in the property might be a bit too much to ask. 

I was thinking if I can talk to my neighbor about sharing the cost (I, the landlord, personally provide labor and my neighbor provide material (e.g. fence pickets)).

You are considering putting a tiny home on your existing property as an ADU or using that money to save up and buy the next investment property and wondering which would be the wiser choice.I think ADUs can help provide additional, much needed, housing.

I interpretttev @Alan Asriants statement different than you but agree it is not clear   He could be indicating pools, basements, sunrooms do not provide a means for an extra tenant.  

He/she can also provide guidance / consulting throughout the year.Best of luck

He could provide you with some good insight in and around the area!

As for non-bank loans, I'm familiar with a loan program that provides 100% financing, but it requires a minimum 650 credit score and proof of funds covering 12 months of interest.

Now the post test reveals I have pvc sewer line leaks under the concrete foundation. plumber has found multiple breaks in the line which need to be repaired and has provided an estimate for tunneling under the house and replacing entire 45ft main line!

Shared housing provides affordable, flexible rental options for young professionals, remote workers, and students.As shown above, co-living properties have more demand than traditional two-bedroom units and appeal to a wider tenant base.2.

My conclusion is that take the provided ROI calculations from REI as purely estimates.