We are building a home and our builder is charging us builder mark-ups for every upgrade we do. If we choose anything off the standard list-including just a change in the type (same brand) of faucet, he charges us 25% in addition to the cost of the upgrade itself. We are doing quite a bit of upgrades and this was never discussed when we put a contract on the home, nor was it discussed when we went in with our interior designer to make all the selections, he just presented us with a bill. What is the industry standard-no one reliable seems to know. Do we have any recourse or do we just have to pay?