I found this company through a web search for house cleaners in Ajax. After contacting all of the cleaners on the list, "The Maids" and "Molly Maid" were the only ones to get back to me.
I chose The Maids as they had a $50 coupon for first time customers (or something like that... check their site). It was easy to book them and was given some good advice as to what services I would need based upon my requirements.
I was preparing the house for sale and needed a full house clean. And boy did they clean, but it wasn't cheap! A full house clean for a house with two cats and a hairy dog cost $520ish. But they cleaned everything. After I saw the bill I checked; ran fingers over every picture frame, the ceiling fan, light fixtures... The place was never so clean. The railings felt like they had been conditioned, soft and smooth...
Ultimately, I could never have come close to this level of clean if I had set out to do it myself. The cost was high but I got what I needed.