Sonia's basement apartment is a great place to stay. Location is ideal, well connected by public transport, and the places you need to go are often within walking distance, like Dufferin Mall (Walmart, No Frills, Marshall's, etc.).
We did have a few issues with the place, which will mostly only affect people staying for long periods. The heating was on a timer that we couldn't change, and we were asked to keep windows closed when it was cold outside, so the place was always too hot. We had issues with ants - small amounts, ant killer dealt with them easily, but then they would show up again after about 2 weeks.
Finally, beware the advertised cancellation policy. When we booked, the policy said that we could shorten the trip, as long as we gave 30 days notice. We did this after finding a permanent apartment, and Sonia wasn't happy about it. She insisted that she couldn't find cleaners in time, so she cleaned kitchenware herself in the last week, and asked us not to use them.