1) The house has poor drainage
This is the most common problem found by home inspectors. To improve drainage, you may have to install a new system of eavestroughs and downspouts or have the lot re-graded to better channel water away from the home.

2) The house has faulty wiring
An insufficient or outdated electrical system is a common problem, especially in older homes. This is a potential hazardous defect and not to be taken lightly. You may have to replace the entire electrical system, or at least part of it, to bring the home up to todays standards of safety.

3) The roof leaks
If the ceilings have water damage, older or damaged shingles or improper flashings may have caused it. Its inexpensive and relatively easy to repair shingles and small amounts of flashing, but if the roofing is old, you may face a much larger expense to replace the whole thing.

4) The house has an unsafe heating system
An older heating system or one that has been poorly maintained can be a serious health and safety hazard. You may have to repair or replace the old furnace. This is a major expense, but new furnaces are more energy-efficient, which will probably save you money down the road. If your heating system is anything but electrical, install carbon monoxide detectors in a couple of locations in the home.

5) The whole house has been poorly maintained
Examples of poor maintenance include cracked or peeling paint, crumbling masonry, broken fixtures or shoddy wiring or plumbing. You can easily repaint a wall, replace a fixture, or repair a brick wall, but makeshift electrical or plumbing situations are serious and potentially dangerous problems. Replace any such wires and pipes.

6) The house has minor structural damage
Minor structural damage means the house is not likely to fall down, but you should deal with the problem before it becomes more serious. Such damage is usually caused by water seepage into the foundation, floor joist, rafters or window and door headers. First you need to fix the problem (a leaky roof for example) then repair or replace any damaged area. The more extensive the damage, the more expensive it will be to repair.

7) The house has plumbing problems
The most common plumbing defects include old and incompatible piping materials and faulty fixtures or waste lines. These may require simple repairs, such as replacing a fixture, or more expensive measures, such as replacing the plumbing system itself.

8) The houses exterior lets in water and air around windows and doors
This usually does not indicate a structural problem, but rather poor caulking and weather stripping that require relatively simple and inexpensive repairs around windows and doors.

9) The house is inadequately ventilated
Poor ventilation can result in too much moisture that wreaks havoc on interior walls and structural components. It can also lead to allergic reactions. Install ventilation fans in every bathroom if there are no windows and regularly open all windows in your home. To repair damage caused by poor ventilation, you may only have to replace drywall and other inexpensive finishes. If you have to replace a structural element, it will be more expensive.

10) The house has an environmental hazard
Environmental problems are a new growing area of home defects. They include lead-based paint (common in homes built before 1978), asbestos, formaldehyde, moulds and contaminated drinking water. You usually need to arrange a special inspection to determine environmental problems and theyre usually expensive to fix.