With a little more effort than scanning the rooms you may find more wrong than what you were told.  You should look for things most people don't think about looking into when buying a home. Bring a few tools and a flashlight. Look at the electrical outlets, breaker panel or fuse box, piping, attic insulation, central air ducts, and signs of recent repair work for hidden problems. Of course this doesn't mean you forgo bringing your own inspector if and when you are seriously considering making an offer.  

Be aware of do-it-yourself home improvements. In one case, a buyer ended up with a home in which the previous owners enclosed the garage to form a living room. The seller did the work himself. All additional electrical wiring was run to one side of the breaker panel causing the breakers to trip when the buyer ran the vacuum and something else at the same time. Additionally, the roofing wasn't sealed properly and so there was water leaking into the attic. The electrical outlets and wires were in such bad shape they began sparking and smoking. Some home improvements are minor enough to handle yourself but when it comes to electrical, roofing or any repair that normally requires a licensed professional you should ask the seller who handled those areas of the improvements.  

Be aware of home improvements done by incompetent contactors. In another case, seller was an elderly woman and she had just had the roof replaced due to hail damage. It was covered under her policy but being the cost conscious senior that she is she hired a local company to do the work and saved a few hundred dollars. When she sold the house neither she nor the new buyer knew of the poor roof workmanship.  An inspection was done but the roof passed.  Apparently the issue was not apparent unless you walked over the area. At closing the seller handed over all the warranties on the appliances, which included a one page Xerox copy on the roof replacement. The buyer was never able to reach the contractor and has had to hire another bonded contractor to re-do the roof.