The general expectancy of properly installed products that are well maintained:

Dishwasher – 10-12 years (Keep drains clear of debris by pre-rinsing dishes)
Range – 19 years gas, 17 years electric, (Keep area directly below range lined with foil)
Garbage Disposal - 6-15 years (Avoid contact with hard objects; use cold water)
Bathtub – 50 years cast iron, 10-15 years fiberglass
Water Heater – 14 years electric, 11-13 years gas (Drain 3-4 gallons from tank each year)
Wood Deck – 15 years (Paint or preservative each two years)
Roof – 15-30 years asphalt, wood shingles and shakes (Shakes preserved every 5-7 years), 50-100 years slate and tile, 5-15 years rolled, 10-20 years tar and gravel
Siding - 50 years vinyl, 20-50 aluminum, 10-100 years wood (depending on moisture)
Sink – 8-10 years enamel steel; 25-30 years enamel cast iron or porcelain
Counter Top – 10-15 years laminate, lifetime ceramic tile
Exterior door with protected overhang – 80-100 years
Garage door opener – 10 years
Cooper wiring – 100 years
Sealer, silicone and waxes – 1-5 years
Paint – 5-10 years wall and trim, 7 years exterior
Ducts – 30 years galvanized, 15 years plastic
Swimming Pool – 18 years
Trash Compactor – 8-15 years
Wallpaper – 7 years
Carpet – 11 years
Brick, Stone Wall – 100 years
Gravel Walk – 4 years
Concrete Walk – 24 years
Drywall –30-70 years
Microwave – 11 years

If the appliances and materials in your home exceed this time, it may be necessary to replace the worn out products.  Your Real Estate Agent can explain the best way to proceed.