Follow this steps:
1) Go to your family doctor and ask for a sleep study test. Your family Doctor will refer you to a specialist who usually works at the sleep clinic.
2) Do the one night sleep study at the sleep clinic. They will connect lots of wires into your head, face, chest, arms and legs and will monitor your sleep thru the night. That is the best way to know what are your sleeping problems and if you have apnea how bad it is.
3) If you have apnea the doctor will prescribe you a cpap machine with the adequate pressure for you and he will advise you on what kind of mask to get depending how you sleep (side, back etc) and the shape of your face.
4) If you are in Ontario government will cover 75% every 5 years and regardless what model you want it will cost you $250 from your pocket. I dont have experience with online stores but I do have a lot of experience with stores around GTA and a lot of them will try to sell you stupid and unecessary packages some of them will have the guts to tell you they cant sell the machine if you dont get the package. In my experience Medigas is more straight forward with the prices at least the one at Warden and Steeles.
5) And finally dont blind buy the mask, go and try the mask for at least 20 minutes at the stores, they do have rooms with recliner chairs where you can go and try the mask, not just the mask but the correct size of the mask. Some stores like medigas have a 30 days free returned or exchange for a different mask, dont stop using your CPAP machine just because you didnt like the mask...go and change for a different model!. Or if you wake up with a headache, dry mouth or weird sensation in your eyes go and see your doctor again, it may be a pressure problem or leaking mask problem. Dont stop until you find your sweet spot and I guarantee you will wake up way way better and with more energy.
People do your research and dont let this stores get you. I just change my resmed 9 elite for the newest resmed airsense for her, from my pocket $250. I called and visit lots of stores around durham and gta and my god bunch of scammers are most of them out there, be careful. Sorry for this long post. Cheers.