I'm not so sure an immigration consultant is always the best answer. Why pay one if you dont have to? They can cost thousands of dollars to complete applications you can fill in yourself.
My family came to Canada and I completed my own application, a friend of mine paid 4000 pounds to a consultant to do the same thing I did and I got my visa within 12 months.
My mother came over to visit, and the long term plan was for her to stay she was going to go through the sponsorship from outside Canada.
I would be asking what ties your father has back at home, we sponsored my mother from within Canada under Humanitarian and Compassionate Grounds and she was accepted. The finances made a big factor as she was not and has never been financially dependant on the Canadian welfare system and that is their biggest concern when considering these cases.
Be wary of people who always seem to point people towards consultants/lawyers. I agree they have a valuable part to play, but my friend saw a lawyer who gave him the big story of how he would get him a visa for sure etc etc .... then when the money was handed over he was told he would have to pay an extra 500 pounds if he was successful. And before anyone comes back with any smart comments .... the lawer was and still is a highly respected one and regulated.
Always explore all avenues before handing over your hard earned cash. I spoke with one guy who gave me advice over the phone, a half hour chat for 100 pounds and then said it would be 250 for each half hour after that. I called him from UK to Toronto and he was nationally advertised. In the end I got so many different stories I took the risk and did it myself.
The forms are easy to fill in and why pay out if you dont have to. You just need to be sure you can afford to make the move and that you have all the information you need. It can take hours and hours to go through these forums asking questions, but it may be worth it. You also get conflicting answers, some people wont be honest, others appear to be on some sort of crusade ...... You need impartial advice and help.
All I did was look at the forms and thought how I could evidence each question asked. Then I did my research, if I got conflicting answers I explored further. I spoke with CIC direct I even travelled to London and went into the Canadian Embassy. They had no financial motive in their response. At the end of the day if you can do it great, but if you cant .... why pay soemone who gives no guarentees.
Good luck, I think you can do it just ask ask ask ... and dont give too much money up easily!! you can find people with honesty and integrity who will help for free or a minimal fee.
If its a question you have, then it costs nothing to answer for free, if it involves someones expertise that they have paid money to learn or gather over years of experience, then fair enough they should charge a fee for that, but it doesnt mean you have to pay if you dont need to.
Best of luck I hope it works out for you.