Call me crazy, but I like my houses like I like my wine. Scope the sewer line. Check the roof and plumbing for leaks. See if the floors sag. Check for settling (indicated by gaps in the door frames and cracks in the plaster/drywall). Check to be sure walls are plumb. Look for any cracks, moisture or decay in the foundation, especially if it's brick or stone. Make sure the lot has drainage/isn't in a depression or flood prone area. Smell and look for mold, termites, rodents, birds, bats, and critters. Check electrical, not just for knob & tube but also fuse boxes, FPE panels, anything less than 100A main, signs of arcing (black burns around an outlet or breaker), aluminum wiring, etc. Windows can be a big expense that is often over looked. So is maintaining or removing mature trees. Utilities will be more if it's poorly insulated, with dated appliances. Lead paint and asbestos aren't too big a deal but you should know the scope of remediation project you're getting into. Often times, these completely addressable issues can help you negotiate a better price based on what you find during inspection. You will have to do some work on an old house, but working on old houses is fun. I'd prefer an old one with good bones to one built last week out of glued together sawdust, nearly identical to it's neighbor. Just be ready to make some repairs, and whatever you do, don't buy in a historic district!