My Latin American friends working in construction would not believe this, they are paid crap, and is the American construction company owner who pockets most of the money.
Depends on what they're working in. A certified plumber, electrician, furnace/gas, HVAC specialist, all command market rates set by tgeir associations. Tilelayers, bricklayers, carpenters and cabinet makers also have set rates. There isn't much left that's unregulated, perhaps framing, drywall/plaster, hardwood/vinyl flooring, painting and landscaping.