My guess is that your contractor suspects that you will not be very happy with the larger window after you see the bill. It will be necessary to tear out part of the interior wall, and install a new header, above the new window. Its not particularly difficult to do, but the cost of new sheetrock, finished to match the existing wall, must be added in.

I can't see the inside picture, but from the outside the window looks odd, to me. It looks like a poor patch job where the builder planned something larger, but had a smaller window on hand, so made do.

Are all the windows this "sticking out" design? If not, I would put the new one back into the wall if and when you redo it. If you are looking to get more light, I find that the deep window wells in our stone walls let in less light than would shallower windows.

I would much prefer a full size window, but this does need to be balanced against the cost.

If you have cabs near the window on the inside, they may need to be removed to do the work, which will add to the cost and will risk damage to new cabinetry

Not sure what happened to the other pic, but here is another.

I hadn't thought about a patch job! Sounds like what they did. We have been remodelling and fixing all the mistakes they made on this house.

The other windows are flush with the house and do not stick out like this one.
{{!gwi}}