might not be expensive. sounds like the hoses that go to the heater core are leaking and maybe even the heater core itself. for one, the leak on the passenger floor for sure is the heater core or hoses going to it. i would put my money on the hoses first cause they are cheaper and easier to fix. now for the one in the wheel well. try to see if you can tell where it is coming from. you my have to really get in there to see, make sure you take a light. if you can see or feel any slimey stuff on a hose look its an easy fix if not you may have bigger issues. but not worry its more than likely just a hose and i would bet a common hose for both problems good luck | 
