I am of immigrant household..... 1st and 2nd gen.....

The city's median household income of $31,843 a year is well below the U.S. median of $57,652.There are likely many factors that contribute to low incomes in the area, though one of the most significant is employment.

I think that, regardless of the deal you have with the seller, the primary lender that you refinance with may not like you having a 0% equity stake in the property, or very tiny equity position of less than 25%, and may require you to reduce or eliminate the "junior lien" or whatever you want to call it that is this seller carry item. 

And as an overarching question - how should I apply my minimum standards for a household of multiple tenants?

Another option is purchasing land to add a type of tiny home, trailer, RV, Etc. 

Otherwise, we have lenders that specifically allow for "tiny homes" under 600sf.

If your household income is less than $150,000, you can save on taxes without a complicated strategy.

At 599 total heated square feet, the small tiny home will feature an open driveway, 3 bedrooms, 2 bathrooms, kitchen, living and dining combo, all electric, with a full size washer and dryer.

SupplyLas Vegas is unique because it is a tiny island of privately owned land in an ocean of federal land.

If you are living at home, contributing the household (eg paying your parents rent, paying for food) for a few years that may be fine.