Doors are one of the most commonly reused architectural salvage components.
Building a frame opening to fit the salvaged door is more advantagous than finding a door to fit an existing aperture. Consider different hanging methods; hinged, track sliding or pivot hinging.
Glazed or half glazed internal doors can help small spaces feel lighter.
Using Crittall doors internally gives an industrial feel; the metal doors can be re-hinged onto a new timber frame.
Multiple doors can make a cost effective panelling.