Cheapest truck kit in my local model shop is £45 ($72) And that is the Revell Australian rig, which is on special offer. You can get them cheaper on line, but then they kill it with outragous postage costs.
I thought I had a good deal on a Kenworth on Amazon, at £27. Then I looked at the postage - £18.50. It's the kind of stunt that gets pulled on e bay too. Sell it cheap and charge hugely for P&P