If you are comfortable in English language (which will help your IELTS Score and get you a good CRS) you can do away with a consultant.
The instructions on CIC's website are clear and easy to understand. For any doubts this forum is a great place to network with people around the world who can help.
I did not use any consultant for my application and the forum helped me all the way.
Consultants in UAE will charge you around 8-10k AED for 'guidance'. The same is available for free on this forum. Save your money and start spending time on the forum to research and follow the steps. I visited 3 consultants in Dubai just to get an idea and in the end realised that all of them said what I already knew from the forum.