Where are all these small landlords?!

They still exist here and there. Generally speaking, they're cheaper than the big corporate brands but also significantly less responsive because its one guy and his two sons pretending they can handyman their way through a forty unit complex that hasn't had a proper renovation since the 1980s. Because they don't have the state-of-the-art fuck-you-rent-goes-up optimization computers, they get a lot of lower income and longer term tenants. But they're also prime for buy-outs from folks with infinity borrowed-at-0% financing.

So what you'll often see is a large community of people who hate their old small landlord because they have to maintain properties they don't own double-plus hate their new big landlord even harder for jacking up rent to force them out and bulldoze the space.

she was just renting out her basement not hording housing.

Its frustrating, because a lot of this isn't an individualist "hording housing" problem nearly so much as it is an institutional "we only have ranch style housing that sells for $1000/sqft" problem. So while renting your basement is far from the worst landlordism imaginable, it is still functionally profiting from a shortage of housing that your home functionally represents.

Its not her fault. She's just in a position to glean rents off a problem she has no control over, while you are not.

The real problem is for-profit real estate development. Ranch housing is cheap to develop and flip when populations are low-but-growing, while big MFUs cost more up front and clear more slowly. But then ranch home prices inflate as MFUs come into higher demand, and you have an incentive to rent-seek and speculate rather than make way for denser development, because why would you not?

In Toronto a chunk of the rental supply is people buying an "investment" condo they rent out (often at a short term loss). Or in college towns usually owners of student housing units own a house or a few houses. They're strictly speaking small landlords, but in my experience they're so much worse to deal with than owners of purpose built rental units.

I had one the last place we lived. They were a real estate agent couple who owned a pair of duplexes, and the first time we met them they happily told us that the duplexes were "their retirement". I've never forgotten how open they were about that fact. It's one of those memories from back when I was a lib that has stuck with me.

They were alright as landlords, friendly enough, maintenance got done pretty quick when necessary. It was wild though, I paid rent one day late one time because I was busy as shit and my partner was out of state for an extended period, so it just totally slipped my mind. The nastiness of the text I got was a bit of a surprise to me. I was still very much a lib at that point, so I was extremely confused as to why a seemingly extremely harmless (and easily fixable!) mistake could lead to such an instant change in personality from a person who had always been friendly to me before.

My mom rents a house to me, since she lives with her boyfriend now

Oh hey, rented out some person' basement gang! I assume you also had no proper ventilation? Wonder if you had to share their shower and kitchen tho lol.

Also my dad was a small landlord for awhile. Well sorta. His wife inherited some rental properties from her great aunt, and my dad styled himself landlord because he did the building managing. It was in her name tho. He told me stories about building managing in a poor neighborhood like it was war trauma lol. Anyway pretty sure they sold those properties off.