Generally, casement windows cost more than double-hung windows. Operable skylights and roof windows cost more than fixed skylights. Arched fixed glass, circles and trapezoids all cost more than rectangular glass. The wood species chosen for the frame will affect the price of your home. Douglas fir cost more than pine.
Recycled timber is more expensive than new timber.
Kiln dried timber is also more expensive. Interior finish affects price. There are also various levels of quality for the interior finishes of your home. These are sometimes customer-driven and sometimes just the way things are traditionally done in a particular geographic area. These grades of finish can affect the price of your home considerably.