Upvote:4
It'll depend where you're flying, what type of flight (multi-leg etc), how busy the season is, and how far ahead of time you're booking. The tighter the time frame or higher the demand, the harder it is.
Of course, the Flightfox hackers until a few months ago were all experts/hobbyists/searchers and you could get a dozen people all trying to beat your price. I liked that, there was a good chance you'd succeed. And back then, if they couldn't beat your price, you got your money back. Annoying sometimes as a flightfox hacker when customers would suddenly come out with a price (as though they'd been hiding it until then) but such was life.
Then recently Flightfox changed their model, now charging for a dedicated 'travel agent' of sorts to check out your flight and help you book. I'm unsure about the new model, as 1) many of us experts have been grounded for now and 2) I've not tried it yet. However some feedback I've seen online has been positive.
However, the past few weeks I've been checking out Darjeelin Expert - a similar site, with price checks - just to confirm you have got the best price. That may be more in line with your preferences, possibly. On both of them you can specify no fuel dumping in your criteria, so it's always possible to avoid those, but that does reduce the hacks that are possible.