You’re missing a lot. For one thing the panels will be totally different. Most C models will have the cluster panel and lack much avionics, engine monitors, auto pilot, etc. Depends on your mission. If you’re looking to do casual VFR weekend flying for 1-2 people, the C is great. If you intend to be doing a lot of IFR, flying more people, etc you may want a later plane.
Age is another factor. You’ll find that C older models are more likely to be run out needing engine overhaul, paint, interior, tank reseal, etc. Many owners discover it’s cheaper to sell the plane and by one the way they want than to refurbish theirs. If you are content with it being an older and likely more worn out plane without upgrades, it’s a superb deal. However you might find that converting the engine, panel, etc to more modern may cost more than getting a plane that already has all that.