UPDATE: after posting my negative review, they responded and are finally planning to complete my simple job in 10 days. Hopefully it's done correctly. They shouldn't need a public complaint to complete a job that was already started, but I guess that's what happened in my case.
I recommend you avoid Casa Bella. They are one of the largest window producers in Toronto, and their products may be less expensive than some of the competition, but you will pay for it in the long term. Their windows are not as energy efficient as they promote, so you'll spend extra on heating / electricity bills , and their post-installation service is quite unresponsive. I understand the COVID pandemic is interrupting many services, and I don't expect anything that would be unsafe or go against public health orders. But their service department was very difficult to get a hold of, and more than 6 weeks after they did send their technicians to take measurements to fix broken parts, I still couldn't get a quote or any sort of additional information. I tried e-mailing the service supervisor and calling the main office, who promised a call back, but no matter who I get on the phone, still no reply. Save yourself the trouble and avoid Casa Bella, or prepared to be frustrated.