I stayed at Kaisar Guest House for 2 nights to attend a concert in Toronto. I was very satisfied, considering it was one of the cheaper options I could find.
The person who checked me in was friendly and great at explaining the house rules. The room itself (room 12), while nothing spectacular, was decent considering the price. It's perfect as a place to sleep in the evening, but not somewhere you'd probably want to linger (which shouldn't be a problem if you're going out and doing things in the city). In my opinion, this makes it perfect for short stays (e.g. 2-3 nights).
There's also a lot of great food places nearby, and it's right next to the streetcar stop which is super convenient for getting to the subway. If you don't mind walking and the weather is decent, the subway is also not too far of a walk.
The neighbourhood can seem a bit "rough", but I never felt unsafe.
My only solid complaint is that you might get woken up by noise. My 1st night was totally fine, but on the 2nd night I woke up before I wanted to around 7am because I could hear loud talking. I was able to go back to sleep right away, so not a big deal for me (plus 7am isn't super early), but something to just be aware of.
Overall, I'd highly recommend Kaisar Guest House if you're looking for a budget-friendly and convenient place to stay in Toronto for a couple of nights.