Recently I had a package shipped by UPS. When the man came he said I owed $49 in brokerage fees, almost HALF of the total value of the $100 item.
Is it reasonable to charge this much?
No, if it's UPS, just call them and complain about the high rate.
I did this and the cut it by half with only a bit of finageling. Remember, you can always go to your local customs office instead, but since this can take a whole afternoon it is reasonable to pay some sort of clearing fee.
It's more like a flat fee, not a percentage. That is, they may charge you $49 to ship a $10 item (of the same bulk, under the same circumstances). And they may charge you the same $49 to ship a $10,000 item.
Now, $49 may be unreasonable, as another poster suggested. But if some lower number X is reasonable, it will likely apply to similar packages valued at $10, $100, or $10,000. After all, they did the same amount of worik.
I once paid about $100 to clear $1400 of merchandise. Part of that number is set by the broker, and part of it is set by the Harmonized Tariff Schedule. The latter part is not adjustable and would be the same no matter which broker you go to.