Since you are only planning on moving to Canada in 2019 you likely have at least 4-5 years before you can apply if you are not moving to Quebec. Once you've established yourself in Canada (6 month-1 year at least) you can apply for a supervisa if you want your parents for longer periods. You will have to pay there health insurance for acute incidents. This is still only for visiting so they will need to keep their home and return.