Before you buy a house, you'll want to have it examined by an experienced, certified inspector. As much as your family members and friends love you and want your best interest, unless they're also experienced, certified inspectors, hire a professional and don't rely on amateur, if well-intentioned, opinions. Here's what the inspector will be looking at:
The foundation is obviously a very important part of a house. The inspector will examine if any cracks in the floor or walls point to structural problems that will get worse over time. He'll also check if the basement is prone to flooding.
The inspector will check the quality of the construction of the house, and whether the wood is still holding up or if it's beginning to rot; if the floors are level; and if the windows and doors close properly. In addition, he'll examine the roof to see what kind of condition it's in. If he determines that it it will need replacing in the near future, you'll either want to get a reduction in the house's price or a different house.
The plumbing of the house --if it's been installed properly, if there are any leaks, or if it's rusting away -- needs to be properly inspected, as you certainly don't need any nasty surprises here, like mildew in the bathroom or worse. The inspection also takes into account the heating and cooling systems, to make sure that the air conditioner is in good condition and the boiler isn't due for an immediate replacement. They'll also be checked to see if they're sufficient to heat or cool the area inside the house.
The inspector will also check that there are no problems with the electricity and that the appliances in the kitchen function as they should.