Beware of an over-insulated home. Sounds weird, but too much insulation will keep air from circulating through the frame and interior of the house. This is a very unhealthy condition, and may cause maintenance problems. The wood is white or red cedar, and has a natural preservative. Expect clapboards to be stained.
Maintenance is about every three years.
This will generally require additional maintenance. Beware of Asbestos shingles. These are easily identified by a home inspection. Be especially careful about vinyl or aluminum siding over wood. If not prepared properly, this could be a situation whereas there is untreated rot that is very difficult to remediate.