Brokerage fees - industry standard?

I've been scanning the 'net to get an idea of an average brokerage fee for
an aircraft (1968 Cherokee 140) valued in the $20,000 to $25,000 range. My
expectation would be advertising the aircraft and acting as initial point of
contact. The aircraft would need to be sold from my home base, not from the
brokerage firm's home base.

I note some agencies provide flat fee based on type of aircraft or selling
price and some do the work for a percentage. I see percentages ranging
from 2.9% to 10%, with 5% being average. Can anyone confirm this as a
reasonable fee?

I'm located in British Columbia, Canada.

.....................
sue thomas