Great Boat,
John,Catalina boats are great, and not just because of the manufacturer. There is a wonderful owner network which is strongly supported by Catalina (and the owner, Frank Butler). Practically anything you need/want/think to do, someone else may have already done and the information is available to help/guide you.I've had my 1988 tall-rig with a wing keel for 12 years and still love it. It is a great boat, and sails very well, points well (tacks through about 110 degrees) and is fast (use 4.5 knots average for cruises), even with a 3-blade fixed prop. It is also very easy to manuever under power (it spins on a dime and can give you change back).If you have a choice, the fresh-water cooled Universal Diesel M25 (xb, etc) is a great engine, very reliable, albeit perhaps a bit noisy/vibrationy (but it's an 'auxillary', so who cares, right?). Although, do pay attention to the raw-water pump/impeller annually (consider a globe brand - run-dry impellor, just in case).I only have a 135 Genoa which at times is overpowered by the main, so a 150 Genoa may be a better match (and is how a friend's 1985 is configured). However, the Tall-Rig has alot of sail area, so all to often (18+ knots of wind) I do/should reef to maintain a comfortable angle of heel (10-12 degrees is optimum), whereas other boats (inclusive of Catalina 30's non-tall rigs) do not have to reef in the same winds.I am assuming you want the tall-rig because of light winds. I actually wanted for the bow-sprit for the better anchor placement, and got the extra sail area as a bonus, albeit not really needed where I sail.However, be prepared to reef and consider a improvement to the reefing system to make it doable from the cockpit (if not already done by a previous owner).Also, be sure to subscribe to the International Catalina 30 association, and read the quarterly Mainsheet magazine, along with acquiring the Catalina 'tech manual' available via the link provided above by Bert. Both will answer virtually any question you might have, which depending on the year you purchase, and previous owner upgrades, will help you do some important manufacture recommended upgrades as well as numerous comfort improvements.ALso, Catalina made improvements and subtle changes to the Catalina every year, so if you have multiple years on your radar screen, check out the above link for info on changes each year (e.g. in 1987, the wing-keel was offered, the 'T' cockpit was introduced, the chart-table was lowered, and the cabin floor was raised, slightly reducing main cabin headroom).Hope this helps... good luck..