What time of year are you going? Why are you limited to < 40 ft - is that budget or are you concerned >40 would be difficult for the two of you to handle? If you are thinking shoulder or low season the boat prices are not that different - a few hundred dollars will separate a 40 from a larger and better equipped boat. Like Baard, I too have a boat managed by CYOA. Mine is a 45 with gen/ac and water maker which makes it pretty ideal for venturing to places with sparse water availability. My wife and I handle her by ourselves just fine and we are by no means expert sailors. So if you and your partner are comfortable with a boat up to forty I can't imagine why the extra size is going to stress you out.