Kitchen cabinets and formica countertops are relatively easy. Sinks are easy, except ones surrounded by tile.
Wood siding is easy but requires patience.
It takes time to pull nails too. Removing bricks in mortar can be easy or difficult, depending on how soft the mortar is. The entire forced-air duct work is salvageable. A garage vehicle door takes an hour or more. Anything that must be pulled off a roof or high place such as ceramic roof tiles, TV antennas, spark arrestors, etc. means a danger of falling.