If your home is filled with old-style brown wooden doors, do not try to brighten them up with paint. The effort involved will not be worth it. It could take three or four coats of paint to cover the brown wood. You're better off simply buying a new white door instead.
When building an addition to your home, make sure to use insurance-friendly materials. Cement or steel buildings present less of a liability to the insurance company in case of fire, so they charge lower premiums for using them. Wood framed buildings will greatly increase your premiums, because these are much more likely to be damaged in any sort of disaster or fire.