As for the cab fare it never cost us more than $21.00 (US, not Canadian Loonies) to take a cab on our last two trips, and that's with a tip (anywhere from $2 to $2.50)
We are cheap but we are coming to terms with the fact that it's really a good idea to take a cab if you are going
from resort to resort or BACK from Downtown Disney from the BC/YC.
For dinner at a Magic Kingdom resort area hotel we would leave early and take the bus to MK (then take Disney transportation/hoof it to the hotel) but on the way back, if we weren't going to the parks and it was anywhere near the time where a lot of people were leaving MK, we would not hesitate to take the cab back to our resort.
Definitely budget for this if you are headed to another resort, as it is well worth it. We even saved ourselves some much needed rest time by taking a cab directly to the POLY for a dinner instead of leaving an hour in advance to take the bus to MK then the monorail to poly. It took 20 minutes from BC pick up to the lobby of the Poly and we felt well rested and ready to enjoy O'Hanna when we got there.
~NM
PS. Thanks to everyone for all the TR lovin!