Currently communication for the purpose of prostitution is illegal as well as keeping a common bawdy house and living off the avails. In general outcalls are legal though you don't want to pick up a lady in a public place as that would be communicating (solicit a lady in a bar or on the street) and incalls in general are a grey area which is going through a court challenge to clarify the laws - as an example a lady that keeps a condo to entertain clients could be defined as keeping a common bawdy house but a lady that rents a hotel room to see one client would be difficult to define as a bawdy house though it's not impossible it could be.
In general the police in Toronto look for exploited and underage sex workers but leave established independents or reputable agencies alone. There is no reason to not be cautious but I would encourage that in any city you visit and not just for legal reasons but because I would hope you want to avoid seeing a lady that has been trafficked or is underage. Use the boards and common sense and you won't have any issues both legally and personally, if however you are seeking an 18 yr old "independent" that offers very discounted dates at a cheap motel or a foreign lady that cannot speak English then you have no way of knowing what you are supporting and it's also possible the police are interested in confirming the lady you are seeing is also not being victimized.
If you feel like doing some extensive reading on the legalities in Canada you can always check out SPOC's website as well.