I have also had a problem with Best Flights, I always check ticket change and cancellation costs before I book, I have had to change a date before but never cancel, unfortunately insurance did not cover the cancellation.
The airline cancellation fee was $150, on Best Flights website (if your read terms) it says their cancellation fees will be a minimum of $169. (which is their deposit) I paid the fare up front - Round figures $1800 plus the 2% surcharge to use VISA. My 14 YO was to visit his dad overseas, his dad was made redundant and had to leave Dubai. We originally wanted to put the fare toward 2 new tickets with the same airline but to another destination. BF said this could not be done. Cancellation fees were $625, I asked for a breakup, 150 to airline 130 to "ticketing" and the balance to BF, it was an E ticket generated by BF. Finally after some backwards and fowards it was reduced to $392 breakup 150 airlines 30 ticket balance BF. I must say there were no cancellation fees listed on the E ticket.
I suggested BF that they advise their cancellation fees "up front" as does STA travel when it say $500+. Comment, we couldn't charge that as some of our fares dont come to $500. From what one could conclude if one pulls cancellation fees out of a hat it is hard to advise the client of what they will be. I do not mind BF keeping their margin but I had a brother in travel and the margin is not $490 on an $1800 ticket
Basically you and I have been ripped off. Don't give up, stay with it.
AVM