1-2K to caulk the windows? I have no idea what that means, but I would inquire on several levels. Why does it require that, what is being caulked, and why wouldn't that be included? It wouldn't be the first time that there were a lack of understanding between the client and the contractor.

Here is what was written in our contract. We live in the northeast, not near any waterfront.

Exterior Notes:

House wrap (Armor Wrap) entire house. Tape all joints air tight. Weather tight window wrap around all windows. Home will be made as air tight as possible for energy efficiency.

Interior Notes:

Paint and caulk all windows, doors and trim (satin white)

"Paint and caulk all windows, doors and trim"

I am not one of the experts on this forum. I can only comment that when I had my windows replaced, my windows contractor did not include painting the trim or the windows screens' frames. He said "I am a windows contractor, not a painter". I had to pay a painter to paint the trim, but the painter did it when I had a bunch of other painting to do in the house at the same time, so it was part of a bigger job. Since it is time-consuming to paint trim, and you have to be meticulous to do it, I'd expect painting trim would add a great deal to the cost of the windows installation.

Also, some windows come with trim pre-painted at the factory. For doors, I would only buy a door that was pre-painted at the factory. Just MHO.

Any window install should come sealed as standard. The extra costs might be in some additional finishing, like the flashing tape or the painting mentioned.

You're builder should be taking care of all of this. The customer. Who payed extra make have had different circumstances than yours , but there should be no upcharge. I would make sure they flash the Windows correctly and they operate and seal correctly before they foam them in. Have you directed your questions to your builder?

There are many different lines of Kasson and Keller Windows, not familiar with them or sure which line you're looking at.