I always recommend my buyers to call in an electrician to check the fitness of the electrical system and do repairs/upgrades where/when necessary. This holds true for most homes but especially older homes. Wiring and metal are subject to the elements and time and could become a fire hazard.
Very often I see loose wiring connections in service panels in the homes I inspect. The screws that hold the wire in the breaker tend to loosen over the years due to expansion and contraction when voltage passes through the wire, The steel screw expands and contracts at a different rate (as all metals do) than the copper wire, and they loosen.
I have also found loose wires in newer service boxes because the electrician doesn't check his work. I found a screw in a service panel yesterday in Bohemia that was so loose is was arcing! (shooting sparks)
Your service panel should be checked semi-regularly, especially if you have older exterior wiring from the point of connection on the house to the meter, and onward to the service panel.
I often see rust in service panels due to deteriorated insulation on the exterior service wiring, and have seen breakers completely rusted - which is a serious fire hazard! -Ray