New vs Old
One of the unique features of the Catalina30 line that now has around 7000 boats made, is that they have evolved over time as knowledge and experience has been gained. Not only have there been major changes for the MKII, MKIII and the C310 but also more importantly, the factory incorporated minor changes in the middle of production run years.You can save money buying an older model but as you get to know the boat and learn more about how later models have been improved you will want to incorporate the improvments into your boat. So you will end up spending more later and if you are like me you will try to save some money by doing the upgrades yourself. Instead of sailing you find yourself at the dock installing upgrades.Of course, the newer boats will cost more upfront but will not need the mods that the older ones need. (As an example of a couple of recommended mods to the early boats: chainplate attachment upgrade kit, available from the factory, tabbing the bulkheads to the sole, straight traveler instead of curved, storage areas behind settees, etc.)Personally, I chose a MKII (an '89)that I am very happy with. Nearly every time I've heard someone recommend an upgrade for C30's (alternator bracket that doesnt crack the timing cover, or larger, 3" heat exchanger to prevent overheating, etc) I've been pleasantly surprised to find that the factory had already made the changes on my boat.In summary, I say go with the newest boat you can afford. I decided early while shopping for mine that I didn't want anything older than the '87 (thats when they introduced the MKII). I liked the larger T shaped cockpit and all the features that weren't included on the old MK1. When (if) I move up to the C36 I would only consider an '87 or newer.