If you are in US pay them in US dollars. Sent them a draft from the bank (NO personal checks ) will be accepted. if you got confused about how much to pay it should be written side by side (in US dollars and canadian dollars). I know it was 575 for landing fee  and 325 application fee in US dollars back in old days....Do not go through lawyers. its straight forward.....No need to waste your money If you are qualiofied. The Lawyer is NOT going to expedite your immigration process anyway