So many issues ..

If it is an operating lease right now (im assuming so) then the future purchase option is a future matter - dont worry about it now. If you do buy it out, it will just be a regular used car purchase - although perhaps with a predetermined price.

CCA (Capital Cost Allowance) is a tax issue for assets you actually own.  If you have a vehicle operating lease then you do not own the vehicle - there will be no CCA.