Laptop repair companies are disappearing for another reason, too... Brand new laptops are cheap. If your product is cheap to buy, it's harder to make money repairing the product.
Well, of course they would bill more. You're essentially paying for all of the neurotic clients who are going to be fussy about the whole process. On top of that, what if it's not the heater and something else? Means you've just wasted extra time trying to fix it.