Oh no.... sorry.... no pun intended...
It just seems to me that a lot of young folks (not that I think you're old

) are posting in this forum.
I just wanted to let you know... just in case
Usually all the big rental places are present at the airports in Canada, and I'm sure this is also the case in Halifax.
You'd be well advised though to book a car ahead of time.
Just for your info....sometimes there is still not the car available you like even if you booked.
They usually don't take it very seriously with that in Canada.
I once booked a midsized car in Calgary ahead of times and ended up with a full blown Chevy Suburban.
AVIS, Hertz, Alamo ... are some names that you should google.
Good luck and have a great trip.
The East coast is beautiful.... very rural but nice and relaxed.... and the seafood is the best..... even McDonald has sometimes a lobster-burger
If you like seafood.... try a 'Boston clam chowder' .... its soup..... I could kill for it

...
Cheers,
Marc