We used our county's room rental lease agreement, because the people at our local REA shared with us that the courts prefer those, and then supplemented with some of the documents from the book.

Doing it now before you know your tenants is much easier to do.Some may suggest that long term tenants are golden however tenants that pay under market requiring the owner to supplement their rents are a definatly a liability not worth keeping.Your other option is to place the best interest of the tenants ahead of your business and lose money. 

Now I'm not saying you should install that solely because this tenant complained but I do feel that some sort of supplemental heat is necessary in any finished basement space.

I would tell them it is what it is and they are welcome to supplement the air conditioner with portable A/C or window units.

So rentals but I would look at flips.I own my owe business (FX Company for films) and it's slow in the winter so I looked into real estate to supplement my income and keep me from going couch crazy.

I'll use my passive income to supplement me in the early months but will want to get to a point where my passive income goes back into real estate again.

Less if we can make more cash-flow per monthNow, where it can get interesting is any other ways we opt to supplement that income.

In my experience the portable heat pumps do not do as well as ductless in cold weather and I supplement the portable heat pumps with a construction heater in my own home.

Speaking as a US urban homeowner, supplementing our retirement income by running 2 Airbnb units in our 2-family home...The "hotel industry" includes a ton of low-paid workers. 

My spouse and I are interested buying and holding single families and small multi-families to supplement our full time incomes and build our way to financial independence.