If you find a house that seems like it has possibilities, do your own initial home inspection, inside and out, before making an offer. Your intention now is to be alert for obvious deficiencies. Assuming you're not looking for a fixer-upper, too many of these may be a reason to eliminate this house from further consideration.
Note: This is not meant to replace a professional home inspection. Once you make an offer on a house, you'll want a licensed home inspector to go over it with a magnifying glass.
Your initial inspection
Foundation: Look at the base of the walls and the ceilings in each room. Are there obvious cracks or apparent shifts in the foundation? Do the same around the outside. Are there any trees encroaching on the foundation?
Lot: Does the drainage appear to be away from the house? Are there any obvious soggy areas?
Roof: What is the overall condition? When was it last replaced? Are there any trees encroaching on it?
Exterior: Does the house look like it will need repairs or repainting soon? Are gutters and downspouts firmly attached? Are there loose boards or dangling wires? Is there asbestos in the exterior material, which would require added costs if it needed to be repaired or replaced?
Attic: How does the interior of the roof structure look? Are there any signs of leaks?
Interior evidence of leaks: Check ceilings and around windows in each room.
Basement: Is there dampness? Adequate insulation? (If there's a crawlspace instead of a basement, you might want to leave this for the professional home inspection.)
Electrical: Do the switches work? Are there any obvious malfunctions? Have the outlets been grounded? Is the panel updated and expandable for additional appliances or a potential remodel?
Plumbing: Any unusual noises or malfunctions? Has the sewer line been scoped to check for potential cracks?
Appliances: If these are included, what is the age and condition of the stove, dishwasher or refrigerator?
Heating/cooling system: Does it seem to do the job? How old is the furnace? If the system has been converted, are the old systems or tanks still in place?
Odor: Is there an odor in the house? Can you detect what it might be and whether it could be fixed? Beware of musty odors which could signal a wet basement.