Please note the information provided below is a layman's definition designed to provide a basic understanding for the general audience.

In the past basic zoning pretty much allowed you to rent a house to 2 unrelated people (family/kids obviously don't count as they are related to the adult(s). 

Immigration plays a big role in this, so it would be hard to predict unless you know what happens with population growth.I think it's still a basic human need, and one that the government can not provide at a reasonable cost.

Definitely looking to add more kid-friendly outdoor seating/climbing wall for families with young kiddos.

Looking for some basic strategies and success/failure stories.

While there are paid plans with more features, the free version is useful for basic analysis and getting a good overview of a property's potential.3.

I've come across several products online that are basically a block with double-stick tape, but I like the tread idea on the block you have. 

Couple of things I looked out for:- Area, make sure it's somewhere that will have stable demand- I stayed away from homes that had a lot of renovations that were needed- During the tour see if you can spot basic issues like if wiring is old or how new is the HVAC system, etc. - If you decide to keep the tenants that are already there see how well they keep the place

He had 4-5 kids, so got a nice S8 voucher for the rent. 

If you do qualify you would basically be refinancing your current Heloc and use the new Heloc to pay it off the original Heloc.